Database Users

Slot_A-B How to Flash Roms/Magisk/Kernel 8.1???

How To Flash Roms with the Ridiculous Slots... yep. You're a rookie again because these things are going to drive you onto a drunken crazy bender... You'll probably wake up in Mexico married to someone you've never met and tied in with the Chicago Mob in debt for a quarter million. THIS IS WHAT WORKS FOR ME. I do the same thing Every time and have done this wrong so many times I've lost count.
Note number 1...
You have or know how to use adb and fastboot basics... if not... Of not Google the Adb and fastboot set up for your devices and/or PC/Laptop etc... There are a lot of forums and Q&A on setting this up to get fastboot cmds running. You should be familiar regardless and at least have the stock flashall.bat for a Google Stock IMG JUST IN CASE. I am assuming everyone is already at the install for TWRP and is working with 3.2.0-0 only. You cannot flash roms without it. Any other version for 8.1 will NOT work at this time...
Note number 2...
Roms will vary. Some may include the vendor image and you don't need to flash it. Some may include gapps and you don't need to flash those... Some may include everything and have you flash to slot_a and that is all. In other words do what the OP says, they built it. They know what's in it and how it works.
Here's the trick... It doesn't mean you can't do these in any other way but you will NOT get stuck if you follow some simple rules...
Roms only flash while in Slot_A
Gapps only Flash in Slot_B
Kernels only flash in Slot_B
Magisk only flash in Slot_B
IMG Flash to Slot_B
TWRP 3.2.0-0 ONLY
TWRP 3.2.0-0 to either slot
Do NOT EVER Flash anything other then TWRP, Rom Gapps and Vendor until GOING through first boot. Yes you can but it increases your issues.
Always always always double check between every install the status of your Overlays folder. Before every rom install Mount System then Go to File Manager and Delete that folder from Slot B before you boot to Slot A to flash the rom. This can hold Data from Magisk and Mods that get all tore up Everytime... It also happens when you reflash Magisk or dirty flash a rom. I'm going to put together a fresh flash below and I'll get into that a little later.
So from stock Google image...
Clean flash... MAKE SURE YOUR LOCKSCREEN IS OFF... No fingerprint set up... Not a pin set up... No pattern set up. If your more secure than swiping up to open your screen your not getting in to TWRP 3.2.0-0 decrypted.
Either... Reboot recovery (you'll be in slot B) if you already have TWRP installed....
Or....If you're just booting TWRP for the first time...from bootloader you fastboot boot (not flash really the terminology is BOOT) TWRP-3.2.0-0-marlin.img (you'll be in slot B)
Read your bootloader screen or go to TWRP 3.2.0-0 Reboot menu to find out which slot you're in.
FLASHING YOUR FIRST ROM...
note... Most are going to require before flashing your coming from stock. Just do it. At least the initial install... Dirty flash or clean flash after that without going back to stock but you don't have to flash the stock image.
Ready... You're in slot b remember...in order here...
- Wipe Data System Cache
- Flash TWRP 3.2.0-0 the ZIP
This is why you can't have your lockscreen on... If you didn't listen just go back to your bootloader and start over with the flash-all.bat. Sorry but I warned you... You can't get anything to flash at this point because you can't decrypt 3.2.0-0.
- Go to MOUNT then make sure your system box is checked
- Go to ADVANCED and then File Manager and make sure you have no overlay folder. If you do... click on it and hit delete from the options on the bottom portion of TWRP.
- HIT HOME and Go to the actual reboot menu choice (Not the swipe reboot system)
-Click on slot_A and then reboot back into recovery. ...NOTE... I usually don't use the reboot recovery option.(reboot recovery seems wonky and doesnt work for me all the time) I reboot system and just hold volume down until I hit the bootloader and the choose recovery in the bootloader options...
You ARE in Slot A now... Right... You can Double check in the bootloader or TWRP in the reboot menu.
- if you really really really like to wipe you can wipe Data system and cache in Slot_A... I never do from slot_a but to each their own.
- Flash rom and flash TWRP 3.2.0-0. Nothing else.
- Reboot back to recovery again.
You ARE in slot B. Yep automatically... When a rom is flashed it goes to the opposite slot. And reboots you there on the next recovery reboot so DO NOT GO change your slot to B unless an OP actually directs you to do so.
So... We're in slot B
- Flash Gapps and Vendor... nothing else until after you boot up.
Yeah yeah... You want to be rooted... Well boot up first and we'll hopefully be able to walk through that too.
Your booted up. Go to your development options and double check to make sure USB Debugging is enabled... Really whatever, you're really pretty safe if you have Your fastboot drivers and they must be installed because you installed TWRP to get this far so if something goes wrong from here we can still always do the flash-all.bat so your phone shouldn't implode and brick out.
Reboot recovery. Yep you're in slot B... You should now always boot recovery to slot_b unless you mess something up and get stuck in a loop. I've seen it but couldn't duplicate. It was always me flashing out of order.
GAINING ROOT... MAGISK INSTALL
- Choose the zip, flash and reboot.
Nothing further needed, make sure it's compatible with 8.1 and at least 15 to 16 are Oreo compatible. Easy right.
Well even when I'm updating... the wonderful Overlay folder can get jacked. I'm pretty sure I've heard it laugh at me as I stuck in bootloop after bootloop... If you delete the overlay folder anytime BEFORE you update to the next version of Magisk you'll be ok
UPDATING MAGISK...
So if you're on 15.3 and you want to get to 16.0 without getting stuck or having issues on boot.
- Reboot from Rom to recovery... You WILL always be in slot B by default.
- Go to Mount
- Mount System
- Go to Advanced and then File Manager, find your Overlay folder.
- Click on the overlay folder
- Click Delete
- Hit Home
- Flash your updated Magisk 16.0
MAGISK AND KERNEL
To get Magisk and a kernel going can give you to madness. It gets a little tricky. But honestly devs have really really improved the process. If you're rooted already most you can flash reboot into the rom reboot to recovery again and then do this again...
- Reboot from Rom to recovery... You WILL always be in slot B by default.
- Go to Mount
- Mount System
- Go to Advanced and then File Manager, find your Overlay folder.
- Click on the overlay folder
- Click Delete
- Hit Home
- Flash your updated Magisk 16.0
For the most part the current kernels do not blow out your Recovery anymore however some do. In fact the only one I know that will is Noexezshades. Probably spelled that wrong but you'll catch my drift if you read his OP.
SERIOUSLY YOU BETTER ALREADY HAVE BOOTED INTO YOUR ROM FOR THE FIRST TIME.. You'll hate your life if you set this up during your initial install.
INSTALLING KERNEL WITH MAGISK
- Reboot Recovery (hahaha. Ha. You turned your fingerprint scanner on... Reboot and turn it back off)
- Flash Magisk
- Reboot
I know... right now you're saying WTF... I didn't flash the kernel. This is just a fail safe... Points in Any Kernel need Root to install... I haven't had issues but really probably because I always flash Magisk first.
If you already had Magisk installed start here.
Now we're going to Flash the kernel. It's going to unroot you so we'll just immediately install Magisk I recommend always installing Magisk after a kernel because it also Patches the boot otherwise there are times when patching the boot.img is required however I believe most DEVs have surpassed that FOR MOST KERNELS.
- Reboot recovery (Dang. You forgot to turn off your fingerprint sensor again, sorry life's rough turn off your lockscreen again)
- Flash kernel
- Reboot system
- Reboot recovery (you might lose TWRP however every Newer version I'm using--- unless noted by the OP--- is working at present)
- DON'T flash Magisk... No dont flash Magisk. If you were following along you can see you need to go delete the overlay folder before you flash Magisk it will almost always go bad at this point if you don't delete the overlay folder
- Flash Magisk
- Reboot.
Hopefully you learned what's happening now in the background. I try to explain things from a user level and do this as part of my daily work every day. I don't understand things unless someone tells me what's going on along the way and keeps me partially entertained...
Talk amongst yourselves or don't post Anything. The goal is to take the issues out of the day to day so the devs aren't getting the questions.

I'm gonna have to read this post a couple of times to get the hang of it. I'm kind of a newbie.
Great post. Thank you for the write up. Helps to understand twrp when dealing with two partitions

When I understand it correctly, for a ROM installation I need to select slot a. (Standard for me). And slot b for Kernel installation and others.
But why my twrp installation was broken? After installation I can't boot to the system and unable to start the recovery, so I must flash the complete system images from Google.
Gesendet von meinem Pixel XL mit Tapatalk

Just for clarity, the OP mentions TWRP-3.0.2-0 a couple times. It should be 3.2.0-0.
Nice write-up.
Sent from my Pixel XL using Tapatalk

pkelly517 said:
Just for clarity, the OP mentions TWRP-3.0.2-0 a couple times. It should be 3.2.0-0.
Nice write-up.
Click to expand...
Click to collapse
It'd be neat if I could edit my post from the XDA app. My screen and back glass broke... then the earpiece blew out so I was awaiting parts and haven't been online
I need to go away from the option of even flashing TWRP at kernel install. As everyone updates their kernels... I see it starts a looping issue now. Everything else is solid.

overlay folder
I am not grasping what the "overlay folder" refers to. What folder do i need to delete any time i flash magisk? I really appreciate the detail in the steps of this guide.

-Happy Feet- said:
When I understand it correctly, for a ROM installation I need to select slot a. (Standard for me). And slot b for Kernel installation and others.
But why my twrp installation was broken? After installation I can't boot to the system and unable to start the recovery, so I must flash the complete system images from Google.
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Click to expand...
Click to collapse
Hey Happy feet.
From the beginning
Reboot recovery from stock.
Wipe data, system, and dalvik
Flash TWRP installer.zip after your wipe
Delete your overlay folder if you were rooted previously.
This is at Advanced/ File Manager/click on overlay and then hit delete.
Hit the HOME button in TWRP
Click on slot A and then reboot recovery
Back in recovery now IN SLOT A
Flash ROM
Now flash TWRP installer.zip again
Reboot recovery... Benzo ROM includes everything so you'd just be rebooting at this point into the Rom so read and reread the OP you downloaded from.
Flash Gapps (if needed for your ROM some have them built in)
After you flash the gapps if needed... then flash vendor (assuming it required from the dev who made the rom (like Benzo ROM has the vendor built in))
You do not have to flash TWRP at this point and can reboot directly into the Rom. If it doesn't boot or you hit a bootloop you did something out of order from the above, or there is something wrong with the Rom itself.
Second part... When I say Flash TWRP I mean the TWRP installer.zip there are 2 different files. The marlin-fastboot image and the Marlin Installer.zip. so if you flashed Twrp-3.2.0-0-marlin.img that is not enough... You have to have the twrp installer.zip downloaded on your internal storage to flash through TWRP and you no longer need to fastboot flash.
ROMs absolutely will erase your TWRP installer.zip and you need to reflash TWRP installer.zip before you reboot after you flash your ROM.
Sorry if I over explained it, not trying to make you feel like you don't know what you're doing, it's just very different than the old school installs.

Mikkey81 said:
Hey Happy feet.
From the beginning
Reboot recovery from stock.
Wipe data, system, and dalvik
Flash TWRP installer.zip after your wipe
Delete your overlay folder if you were rooted previously.
This is at Advanced/ File Manager/click on overlay and then hit delete.
Hit the HOME button in TWRP
Click on slot A and then reboot recovery
Back in recovery now IN SLOT A
Flash ROM
Now flash TWRP installer.zip again
Reboot recovery... Benzo ROM includes everything so you'd just be rebooting at this point into the Rom so read and reread the OP you downloaded from.
Flash Gapps (if needed for your ROM some have them built in)
After you flash the gapps if needed... then flash vendor (assuming it required from the dev who made the rom (like Benzo ROM has the vendor built in))
You do not have to flash TWRP at this point and can reboot directly into the Rom. If it doesn't boot or you hit a bootloop you did something out of order from the above, or there is something wrong with the Rom itself.
Second part... When I say Flash TWRP I mean the TWRP installer.zip there are 2 different files. The marlin-fastboot image and the Marlin Installer.zip. so if you flashed Twrp-3.2.0-0-marlin.img that is not enough... You have to have the twrp installer.zip downloaded on your internal storage to flash through TWRP and you no longer need to fastboot flash.
ROMs absolutely will erase your TWRP installer.zip and you need to reflash TWRP installer.zip before you reboot after you flash your ROM.
Sorry if I over explained it, not trying to make you feel like you don't know what you're doing, it's just very different than the old school installs.
Click to expand...
Click to collapse
Thanks for your help, great explained for an pixel Beginner.
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beezza said:
I am not grasping what the "overlay folder" refers to. What folder do i need to delete any time i flash magisk? I really appreciate the detail in the steps of this guide.
Click to expand...
Click to collapse
Go to TWRP.
Open Mount and click to Mount System
Open Advanced and then choose File
If you find a folder in your root named 'overlay' tap on it (select it) and then click on delete.
If it's not there.... great. You've probably never rooted. It'll cause some bootloops once in a while, sometimes it doesn't matter. It's more important to do this at the point of flashing a room because you most likely will not get a fresh install to boot up if you're rooted.
Quick Note: This file carries over Magisk root data and gets messy as you update Magisk or reflash it.

I tried installing latest magisk on android "P" and was on Slot-B and it wouldnt install, error...
changed to slot-A and then it installed..
Magisk v16.3 (1630)

Thanks for info. good stuff i am new to pixel coming for my old friend nexus 6
just fyi I downloaded and flashed twrp-3.2.1-2-marlin before reading this and just happen the passcode thing for me is not a problem. Had to enter it twice the first time using twrp but now just once. works fine.

I don't give nearly enough appreciation where it's due but I gotta hand it to you... By far the best guide ever! Thank you!

Very good details and advice. I'm having far else problems by following these steps. Thanks for all your work.

commenting here to save this for future.
thank you OP!

hoping this thread is still alive. . . is there a recommended factory image to restore to? do i need to flash the factory on both slots? is it best to flash -the factory system.img on a particular slot? In the end which slot to --set_active=?

And how do the SLOTS come into play for doing a TWRP backup and doing a TWRP restore ?

No signal after flashing rom

Hey guys,
I recently flashed Omnirom and after doing so, noticed I had no signal. After flash, reboot, or resetting Network/Data settings, I'll have data for about 20-30 seconds. I can browse the web, but I can't send or receive calls or messages. Then it goes away completely. It sporadically returns, but drops again quickly.
Carrier is Verizon. My Sim card is still being read so the issue doesn't seem to be there. I've put it back in my Pixel 2 and it's working fine.
At a high level, this is what I've done over the past 12 hours:
1. My bootloader is unlocked. I flashed a new ROM and then it wouldn't boot.
2. I did a Factory reset through Recovery and then it booted into the ROM, where I noticed I had no signal
--Possibly an issue here? This factory reset wasn't done thru TWRP, but the stock(?) recovery. I noticed that after doing this, it wiped everything on my phone, including my Nandroid backups
3. I did another factory reset, still no service
4. I moved sim card from Sim Slot 2 to Sim slot 1, temporarily restored service. Then dropped.
5. I flashed OOS 9.0.12 back, service came back temporarily, then dropped
6. I did a network reset, restored service temporarily, then dropped
7. I reflashed modem, system, and vendor images
Anyone have any thoughts or suggestions? Otherwise, I'm probably going to send my phone back to OnePlus for repair.

Try restoring through the msm tool.

TheRemyx said:
Hey guys,
I recently flashed Omnirom and after doing so, noticed I had no signal. After flash, reboot, or resetting Network/Data settings, I'll have data for about 20-30 seconds. I can browse the web, but I can't send or receive calls or messages. Then it goes away completely. It sporadically returns, but drops again quickly.
Carrier is Verizon. My Sim card is still being read so the issue doesn't seem to be there. I've put it back in my Pixel 2 and it's working fine.
At a high level, this is what I've done over the past 12 hours:
1. My bootloader is unlocked. I flashed a new ROM and then it wouldn't boot.
2. I did a Factory reset through Recovery and then it booted into the ROM, where I noticed I had no signal
--Possibly an issue here? This factory reset wasn't done thru TWRP, but the stock(?) recovery. I noticed that after doing this, it wiped everything on my phone, including my Nandroid backups
3. I did another factory reset, still no service
4. I moved sim card from Sim Slot 2 to Sim slot 1, temporarily restored service. Then dropped.
5. I flashed OOS 9.0.12 back, service came back temporarily, then dropped
6. I did a network reset, restored service temporarily, then dropped
7. I reflashed modem, system, and vendor images
Anyone have any thoughts or suggestions? Otherwise, I'm probably going to send my phone back to OnePlus for repair.
Click to expand...
Click to collapse
Have you wiped the cache?
It's not a hardware issue.

rickysidhu_ said:
Try restoring through the msm tool.
Click to expand...
Click to collapse
I would also try the MSM tool to restore back to stock. Then reflash what you want for a ROM.

rickysidhu_ said:
Try restoring through the msm tool.
Click to expand...
Click to collapse
Scott said:
I would also try the MSM tool to restore back to stock. Then reflash what you want for a ROM.
Click to expand...
Click to collapse
Thanks guys. Using MSM worked.
For those who may have the same issue, I used MSM to go back to 9.0.11 since a few people said they had issues with 9.0.12 such as not being able to unlock it. I restored 9.0.11, unlocked my device, then flashed the 9.0.12 OTA. Issue stayed resolved.
I did try to flash Omnirom again and the issue came back, so I'm curious as to what's happening. I'm going to try another Rom.

Just an update, this seems to happen with any rom I flash now. I tried Omnirom, Pixel Experience, and Syberia OS. They boot up but with no 4g connection. When I use MSM to go back to 9.0.11 or 9.0.12 everything works properly. Not sure what I may be missing?

Out of curiosity, how are you installing your custom ROMs. I have installed quite a few custom ROMs in the last week or so and have not encountered any issues. I use a USB pendrive with an OTG adapter to install my stuff as the phone normally ends up in an encrypted state so the internal storage will not be accessible when booting into TWRP. Here are the steps I use when installing a custom ROM:
01. Boot into TWRP
02. Wipe, then swipe. You can choose to Format Data if you want, but this will erase your internal storage so you will lose your recent pictures and other media.
03. Install full OOS 9.0.11/9.0.12 depending on which version is required for the custom ROM and install TWRP also.
04. Reboot recovery.
05. Install full OOS 9.0.11/9.0.12 and TWRP again to ensure both slots have OOS install on it. Use the same version you installed in step 3.
06. Reboot recovery.
07. Install your custom ROM and TWRP.
08. Reboot recovery.
09. Wipe, then swipe (Do not format; unsure if this makes a difference).
10. Install GApps if needed (ROM dependent) and optionally install Magisk and a custom kernel.
11. Reboot system and then wait to setup the phone.
As stated, this has worked flawlessly for me and I have not run into any issues. Admittedly, I have not tried Omnirom directly, but I have tried Omnirom Treskmod (not available on XDA) and SkyDragon which are both based on Omnirom and did not have issues with either. I have tried maybe 10 different custom ROMs in the last week on so and have not had any problems. Still trying to find the best ROM for me. You could say that I'm a flashaholic.
I hope this helps.
Ooms

dj_ooms said:
Out of curiosity, how are you installing your custom ROMs. I have installed quite a few custom ROMs in the last week or so and have not encountered any issues. I use a USB pendrive with an OTG adapter to install my stuff as the phone normally ends up in an encrypted state so the internal storage will not be accessible when booting into TWRP. Here are the steps I use when installing a custom ROM:
01. Boot into TWRP
02. Wipe, then swipe. You can choose to Format Data if you want, but this will erase your internal storage so you will lose your recent pictures and other media.
03. Install full OOS 9.0.11/9.0.12 depending on which version is required for the custom ROM and install TWRP also.
04. Reboot recovery.
05. Install full OOS 9.0.11/9.0.12 and TWRP again to ensure both slots have OOS install on it. Use the same version you installed in step 3.
06. Reboot recovery.
07. Install your custom ROM and TWRP.
08. Reboot recovery.
09. Wipe, then swipe (Do not format; unsure if this makes a difference).
10. Install GApps if needed (ROM dependent) and optionally install Magisk and a custom kernel.
11. Reboot system and then wait to setup the phone.
As stated, this has worked flawlessly for me and I have not run into any issues. Admittedly, I have not tried Omnirom directly, but I have tried Omnirom Treskmod (not available on XDA) and SkyDragon which are both based on Omnirom and did not have issues with either. I have tried maybe 10 different custom ROMs in the last week on so and have not had any problems. Still trying to find the best ROM for me. You could say that I'm a flashaholic.
I hope this helps.
Ooms
Click to expand...
Click to collapse
Because I had erased all data on my phone, I was doing mostly everything from Fastboot or ADB Sideload in TWRP. So my previous steps were something like this:
1. Use MSM to restore OOS 9.0.11
2. Unlock Bootloader
3. Fastboot to TWRP 3.3.0.2
4. Install TWRP on both slots (ADB Sideload)
5. Reboot Recovery
6. Install 9.0.12 on both slots (ADB Sideload)
7. Install TWRP (ADB Sideload)
8. Reboot System to verify I have signal
9. Reboot Recovery
10. Install custom ROM and TWRP (ADB Sideload)
11. Format Data through TWRP
12. Reboot System (No signal)
I had also noticed that there was some system app or process that was repeatedly crashing, but I couldn't tell what it was because the popup notification would disappear so quickly.

TheRemyx said:
Because I had erased all data on my phone, I was doing mostly everything from Fastboot or ADB Sideload in TWRP. So my previous steps were something like this:
1. Use MSM to restore OOS 9.0.11
2. Unlock Bootloader
3. Fastboot to TWRP 3.3.0.2
4. Install TWRP on both slots (ADB Sideload)
5. Reboot Recovery
6. Install 9.0.12 on both slots (ADB Sideload)
7. Install TWRP (ADB Sideload)
8. Reboot System to verify I have signal
9. Reboot Recovery
10. Install custom ROM and TWRP (ADB Sideload)
11. Format Data through TWRP
12. Reboot System (No signal)
I had also noticed that there was some system app or process that was repeatedly crashing, but I couldn't tell what it was because the popup notification would disappear so quickly.
Click to expand...
Click to collapse
I didn't notice any popups when setting up my device. The only thing I can say is that VoLTE never used to work properly for me on OOS. I had to edit a setting in serial mode to get VoLTE working on my network in the UK. Not sure if it is related at all. I highly doubt it. I noticed in your steps, you have not flashed GApps. I believe most custom ROMs don't contain GApps, only a select few. Is there a reason you are not flashing GApps? I know there are individuals who want to stay away from Google and use Micro-G as an alternative. I believe the minimum is to flash Pico or Nano GApps. I am not sure if there is possibly something in GApps that is related to data and telephony. The notification popup you are getting may also be related to not having GApps. I install the Nano GApps so I can get face unlock working. Maybe try that and then try installing Magisk after if you still have the same issues. You are rebooting the system in your Step 12. Maybe try and reboot recovery first, then reboot system to keep TWRP intact. You could try the steps that I posted. I use a USB pendrive but if you Format Data to clear your internal storage, it should not be encrypted after unless you reboot into OOS beforehand. You should be able to push files directly to internal storage through ADB in TWRP or you can maybe mount the phone on the computer and copy the files across. These are only suggestions. I haven't had the issues you are having but the steps I listed seem to have worked consistently for my. As a note, I have never had to use the MSMTool to get my phone back up and running again. I have used fastboot mode before though.
I hope this helps.
Ooms

TheRemyx said:
Because I had erased all data on my phone, I was doing mostly everything from Fastboot or ADB Sideload in TWRP. So my previous steps were something like this:
1. Use MSM to restore OOS 9.0.11
2. Unlock Bootloader
3. Fastboot to TWRP 3.3.0.2
4. Install TWRP on both slots (ADB Sideload)
5. Reboot Recovery
6. Install 9.0.12 on both slots (ADB Sideload)
7. Install TWRP (ADB Sideload)
8. Reboot System to verify I have signal
9. Reboot Recovery
10. Install custom ROM and TWRP (ADB Sideload)
11. Format Data through TWRP
12. Reboot System (No signal)
I had also noticed that there was some system app or process that was repeatedly crashing, but I couldn't tell what it was because the popup notification would disappear so quickly.
Click to expand...
Click to collapse
Not sure if it helps, but you are doing too many repeated steps. Skip 4 & 5, Format Data before installing 9.0.12. Skip 11. Why are you installing TWRP so many times?

dj_ooms said:
I didn't notice any popups when setting up my device. The only thing I can say is that VoLTE never used to work properly for me on OOS. I had to edit a setting in serial mode to get VoLTE working on my network in the UK. Not sure if it is related at all. I highly doubt it. I noticed in your steps, you have not flashed GApps. I believe most custom ROMs don't contain GApps, only a select few. Is there a reason you are not flashing GApps? I know there are individuals who want to stay away from Google and use Micro-G as an alternative. I believe the minimum is to flash Pico or Nano GApps. I am not sure if there is possibly something in GApps that is related to data and telephony. The notification popup you are getting may also be related to not having GApps. I install the Nano GApps so I can get face unlock working. Maybe try that and then try installing Magisk after if you still have the same issues. You are rebooting the system in your Step 12. Maybe try and reboot recovery first, then reboot system to keep TWRP intact. You could try the steps that I posted. I use a USB pendrive but if you Format Data to clear your internal storage, it should not be encrypted after unless you reboot into OOS beforehand. You should be able to push files directly to internal storage through ADB in TWRP or you can maybe mount the phone on the computer and copy the files across. These are only suggestions. I haven't had the issues you are having but the steps I listed seem to have worked consistently for my. As a note, I have never had to use the MSMTool to get my phone back up and running again. I have used fastboot mode before though.
I hope this helps.
Ooms
Click to expand...
Click to collapse
I had tried flashing GAPPs (ARM64-Nano) and it didn't seem to make a difference. I was skipping that and flashing Magisk just to confirm if I had service first. But would service/signal be dependent on something in GAPPs? I may try your way. I hadn't run into any issues with encrypted storage lately. The last few times I was able to get around it by booting to system first, then rebooting back to recovery.
schmeggy929 said:
Not sure if it helps, but you are doing too many repeated steps. Skip 4 & 5, Format Data before installing 9.0.12. Skip 11. Why are you installing TWRP so many times?
Click to expand...
Click to collapse
I was installing TWRP because every time I restored or flashed, I was losing my custom recovery.

Upgrade path from xXx no limits 10.2 to OOS 9.0.5?

I have seen some simlar posts, but in my case the phone is unencrypted. Currently TWRP3.2.1-1.
I am thinking of going back to stock OOS and reinstalling twrp and magisk.
I have a full backup through twrp and sd backup through adb, so I am not worried about losing anything.
What's is the simplest upgrade path?

kuhnto said:
I have seen some simlar posts, but in my case the phone is unencrypted. Currently TWRP3.2.1-1.
I am thinking of going back to stock OOS and reinstalling twrp and magisk.
I have a full backup through twrp and sd backup through adb, so I am not worried about losing anything.
What's is the simplest upgrade path?
Click to expand...
Click to collapse
Hello, you need to remove your screen lock and clean flash the OxygenOS 5.1.4(you can skip format of internal storage for now) with your new recovery, I recommend this one to flash before flashing 5.1.4:
https://drive.google.com/file/d/1UlTftbe6wooAs4Fp0cjwXlOKmfQHgdfL/view?usp=drivesdk
After that flash magisk(I recommend 18.1) and no verity patch you'll find it here https://forum.xda-developers.com/on...xygenos-4-5-2-7-1-1-ota-t3627003/post72799040
If you can sucessfully boot into 5.1.4 and your internal storage is accessible(don't enable any screen lock security) you are ready now to proceed with dirty flash(you have Oreo recovery now, so delete compatibility.zip) like described here(you can go to 9.0.5 skipping 5.1.7, works for majority) https://forum.xda-developers.com/on...xygenos-4-5-2-7-1-1-ota-t3627003/post72799040
You can update to the latest recovery 3.3.x after you have successfully completed the installation of 9.0.5.

Thank you so much! Sounds pretty straight forward. Now I just need to wait for a time when i will be in critical need of my phone in 6 hours to start this process.

kuhnto said:
Thank you so much! Sounds pretty straight forward. Now I just need to wait for a time when i will be in critical need of my phone in 6 hours to start this process.
Click to expand...
Click to collapse
Good luck, report back if successful or help needed.

strongst said:
...After that flash magisk(I recommend 18.1) and no verity patch you'll find it here https://forum.xda-developers.com/on...xygenos-4-5-2-7-1-1-ota-t3627003/post72799040...
Click to expand...
Click to collapse
will no-verity-op5(T)_V3_treble_.zip work with the magisk 18.1 downloaded from above? the link was in the instructions.

kuhnto said:
will no-verity-op5(T)_V3_treble_.zip work with the magisk 18.1 downloaded from above? the link was in the instructions.
Click to expand...
Click to collapse
Yes, I'm using the same constellation for example:good:

strongst said:
...delete compatibility.zip...
...You can update to the latest recovery 3.3.x after you have successfully completed the installation of 9.0.5....
Click to expand...
Click to collapse
Two MOre questions... I think i read somewhere how to remove compatability.zip, but I will need to check on that. IS there somewhere I can reference? and does this have to do with the unencrypted data partition?
Also I saw a TWRP 3.2.3 that had "nocompat check" IS this something to do with the non-encrypted partition?

kuhnto said:
Two MOre questions... I think i read somewhere how to remove compatability.zip, but I will need to check on that. IS there somewhere I can reference? and does this have to do with the unencrypted data partition?
Also I saw a TWRP 3.2.3 that had "nocompat check" IS this something to do with the non-encrypted partition?
Click to expand...
Click to collapse
To your first question: it's mentioned there https://forum.xda-developers.com/on...xygenos-4-5-2-7-1-1-ota-t3627003/post72799040 and I explained you before
2nd: don't use other TWRPs in any stage, it will be more difficult to troubleshoot
Both have nothing to do with the encryption status of your data partition. It's just a compatibility check from oneplus.

Here is my progress so far...
Downloaded (Some later as I found I needed them):
1. twrp-3.2.3-0-20181031-codeworkx-cheeseburger
2. Magisk-v18.1.zip
3. twrp-3.3.0-0-20190427-codeworkx-cheeseburger.img
4. Magisk-v19.2.zip
5. OnePlus5Oxygen_23_OTA_048_all_1904191531_09adcad0d3e4.zip
6. no-verity-op5(T)_V3_treble_.zip
7. OnePlus5Oxygen_23_OTA_037_all_1807181258_7b4b6.zip
8. Magisk-uninstaller-20190204.zip
Actions:
1. Backed up sdcard
2. NAndroid backup
3. FLashed twrp-3.2.3-0-20181031-codeworkx-cheeseburger
4. Flash suscessful
5. flashed OS - Error - Zip Treble compatability error
6. Remembered I need to remove compatabilitycheck. - but now I realized I tried flashing 9.x.x. I need to flash 5.1.4 per instructions
7. Spent 15 minutes trying to find 5.1.4. FOund it!!
8. Flashing OnePlus5Oxygen_23_OTA_037_all_1807181258_7b4b6
9. Flashed
10. Seemed to work except the failed to mount vendor
11. Wiped Cache..
12. Flashed Magisk 18.1
13. wipe Cache again
14. Rebootsing and crossing fingers
15. Splash screen boot loops then boots to TWRP - Forgot no-Verity
16. Flashing 5.1.4 + MAgisk 18.1 + no-Verity
17. Rebooting
18. Seems to be booting into something...
19. It booted into OS and it shows 5.1.4 of the OOS version
20. Ran MAgisk Manager - did not show MAgisk. but none the less, I am moving forward
21. Checked if internal storage is accessible - Check
22. Downloaded Total Commander
23. Deleted compatibility.zip from OnePlus5Oxygen_23_OTA_048_all_1904191531_09adcad0d3e4
24. Taking nandroid backup - But need to clear more space off my USB - I needed to delete Drone videos my brother took right before he passed away.
25. Forgot to get MAgisk Uninstaller - Downloading now
26. Installed the uninstaller
27. Tried installing 9.0.5 - Error Zip Trible Compatibility error - Invalid zip file format. I feel that I might need to read some instructions
28. Let my try to get back to 5.1.4 GOTO step 16.
29. That got me back to functional - My battery is low so I am stopping for the night.
30. After getting bored I tried installing 9.0.5 - Worked
31. Installed MAgisk 19.1 - Worked
32. Installed no-verity - Worked
OS booted - 9.0.5
I think I might have tried installing the 9.0.5 form the usb stick perhaps that did not have the compatability.zip removed. TWRP sometimes has me in USB and other times in the phone. Perhaps I selected the wrong thing????
Working well now

@kuhnto so you've got what you need?

strongst said:
@kuhnto so you've got what you need?
Click to expand...
Click to collapse
Yep! Everything is updated. I posted my effort for posterity for anyone else doing the same.

Instructions installing Lineage

Hello,
this is my first time installing a custom ROM, so a want to ask if I can use the original lineage instructions from their website for installing the https://forum.xda-developers.com/oneplus-6t/development/rom-lineageos-16-0-t3897334 ROM on my new 6T.
Do I have to take care of something special, are there differences in the installing process?
Better asking before then......
Thanks!

I haven't tried Lineage OS. I believe it is based on AOSP. I am currently running HavocOS which is also based on AOSP. Practically all custom ROMs I have tried have required ensuring a stable version of OOS has been flashed to both slots before installing the custom ROM and then GApps. I would recommend reading a thread from a few custom ROMs to familiarise yourself with the process as I believe it should be the some process for most. I would also recommend backing up your internal storage beforehand as there may be a chance that you'll need to format your internal storage to get around encryption issues. In some cases I have had the phone reboot back into TWRP constantly if the storage wasn't wiped first.

Due to the differences in encryption, here is the way I always install AOSP when bouncing back and forth between OOS and AOSP. I haven't tried not formatting data in a while, so it may work without these days, but it didn't use to.
- Backup everything to the PC, so you will need to copy all your data over.
- Sync all your accounts, etc.
- In TWRP format data. Reboot recovery
- Factory Reset.
- Flash Lineage
- Flash TWRP Installer
- Reboot to Recovery
- Flash Lineage (This is only the first time, to get the AOSP rom on both slots, only do this for the first install)
- Flash TWRP Installer (This is only the first time, to get the AOSP rom on both slots, only do this for the first install)
- Reboot to Recovery (This is only the first time, to get the AOSP rom on both slots, only do this for the first install)
- Flash Gapps
- Flash Magisk
- Reboot to System.
- Then you should be able to setup the device, copy everything back over. Restore your data.
After this you should be able to update Lineage as normal.
- Reboot to recovery
- Flash Lineage.
- Flash TWRP Installer
- Reboot to Recovery
- Flash Gapps.
- Flash Magisk.
- Reboot to system.
- No loss of data, or anything.

OhioYJ said:
Due to the differences in encryption, here is the way I always install AOSP when bouncing back and forth between OOS and AOSP. I haven't tried not formatting data in a while, so it may work without these days, but it didn't use to.
- Backup everything to the PC, so you will need to copy all your data over.
- Sync all your accounts, etc.
- In TWRP format data. Reboot recovery
- Factory Reset.
- Flash Lineage
- Flash TWRP Installer
- Reboot to Recovery
- Flash Lineage (This is only the first time, to get the AOSP rom on both slots, for updates, only do this for the first install)
- Flash TWRP Installer (This is only the first time, to get the AOSP rom on both slots, for updates, only do this for the first install)
- Reboot to Recovery (This is only the first time, to get the AOSP rom on both slots, for updates, only do this for the first install)
- Flash Gapps
- Flash Magisk
- Reboot to System.
- Then you should be able to setup the device, copy everything back over. Restore your data.
After this you should be able to update Lineage as normal.
- Reboot to recovery
- Flash Lineage.
- Flash TWRP Installer
- Reboot to Recovery
- Flash Gapps.
- Flash Magisk.
- Reboot to system.
- No loss of data, or anything.
Click to expand...
Click to collapse
Thank you for your answer, everthing worked fine for me installing Lineage, I did it exact the way you posted.
This double flash confused me at the beginning but as you described you have to do it just once.
So, thanks a lot and sorry for my late answer.

KKF32 said:
Thank you for your answer, everthing worked fine for me installing Lineage, I did it exact the way you posted.
This double flash confused me at the beginning but as you described you have to do it just once.
So, thanks a lot and sorry for my late answer.
Click to expand...
Click to collapse
Glad it worked out for you. The A/B slots are new to a lot of people still. The biggest thing to remember is when you flash a ROM you are flashing to the opposite slot. So if you are on Slot A and you flash a ROM, you are flashing Slot B. When you reboot to recovery it will switch to Slot B so you can install Gapps, Magisk, etc. to Slot B where your new ROM is installed. (Gapps, Magisk etc, flash to the current slot, not the opposite slot. )

Flash custom ROM

From 6T (purchased from oneplus.com), any time I follow the instructions for how to flash one of the custom ROMs, I get stuck at the bootloader with no working rom.
I was able to use the MSMTool to restore to 9.0.13. I upgraded a few times flashing OnePlus6TOxygen_34_OTA_024_all_1909112343_9fd6e0057b8747dc, which works, but when I try to flash a custom ROM, I cannot get past the bootloader. I say a few times because I've tried this for a few days now with no success.
Most recently, I used the Flash-all.bat inside 10.3.0-OnePlus6TOxygen_34_OTA_042_all_1912142031_d9ef3-FASTBOOT
I am currently on 10.3.0, with twrp-3.3.1-31-fajita-Q-mauronofrio installed using the fastboot flash boot_a twrp-3.3.1-31-fajita-Q-mauronofrio.img then fastboot boottwrp-3.3.1-31-fajita-Q-mauronofrio.img commands from fastboot.
I can then install Magisk 19.4 or 20.3, however again when I try to flash a custom ROM, I cannot get past the bootloader.
What am I doing wrong?

When you 'fastboot boot' twrp, you can't flash twrp as .img file after that..... (There is no recovery partition on our phone, only a boot one)
If you flash a twrp img it will overwrite boot partition with only twrp and no kernel... Basic knowledge. Once temporarily booted in twrp by 'fastboot boot' command you must flash the installer, meaning the .zip file.
Then reboot your phone in twrp and flash whatever you want
Always latest versions of Magisk, why flashing a deprecated 19.4?

Striatum_bdr said:
When you 'fastboot boot' twrp, you can't flash twrp as .img file after that..... (There is no recovery partition on our phone, only a boot one)
If you flash a twrp img it will overwrite boot partition with only twrp and no kernel... Basic knowledge. Once temporarily booted in twrp by 'fastboot boot' command you must flash the installer, meaning the .zip file.
Then reboot your phone in twrp and flash whatever you want
Always latest versions of Magisk, why flashing a deprecated 19.4?
Click to expand...
Click to collapse
I was having an issue with the boot command in 10.3.0, which is how I found the flash command, and using both of those seemed to work (at least get me into twrp).
Now I am able to just run fastboot boot twrp-3.3.1-31-fajita-Q-mauronofrio.img and it works.
I was using 19.4 because somewhere in here someone mention twrp not working with magisk 20.3.
I've had no issues with 20.3 and twrp, so I will continue to use 20.3
The steps I use to flash a custom ROM (after twrp is installed)
1. remove the lock screen security from the existing ROM
2. boot straight into recovery from the existing ROM
3. wipe Data, Cache, and Dalvik by swiping right to factory reset from the wipe menu
4. flash the ROM from internal storage using the Install button
at this point I've tried a couple of approaches including a reboot here to see if the ROM flashed, and also installing twrp right after flashing ROM so that I will have a working twrp install.
Either way, I can never get past the bootloader.
Am I performing these steps correctly?

s7itch3s said:
I was having an issue with the boot command in 10.3.0, which is how I found the flash command, and using both of those seemed to work (at least get me into twrp).
Now I am able to just run fastboot boot twrp-3.3.1-31-fajita-Q-mauronofrio.img and it works.
I was using 19.4 because somewhere in here someone mention twrp not working with magisk 20.3.
I've had no issues with 20.3 and twrp, so I will continue to use 20.3
The steps I use to flash a custom ROM (after twrp is installed)
1. remove the lock screen security from the existing ROM
2. boot straight into recovery from the existing ROM
3. wipe Data, Cache, and Dalvik by swiping right to factory reset from the wipe menu
4. flash the ROM from internal storage using the Install button
at this point I've tried a couple of approaches including a reboot here to see if the ROM flashed, and also installing twrp right after flashing ROM so that I will have a working twrp install.
Either way, I can never get past the bootloader.
Am I performing these steps correctly?
Click to expand...
Click to collapse
I don't know I don't flash custom ROMs anymore, too old for that stuff and need my time for me.
There are specific instructions for each custom ROM it's better to ask in dedicated threads, some of them need to have OOS in both slots before, some of them need to be fleshed in both slots. Normally you eventually wipe things, flash the ROM and twrp to keep it, then reboot to twrp (necessary to boot on the slot where the ROM is actually fleshed, which is always the non active slot, which become the new active slot) and flash Gapps and Magisk ( because Gapps and Magisk can be flashed only in active slot) then reboot system

s7itch3s said:
Am I performing these steps correctly?
Click to expand...
Click to collapse
I've updated these instructions here, they are the same, just added to them really.
This is how I install Lineage 17. (If you are doing 16, replace 10.3.0 with 9.0.17, and the Q image of TWRP with the Pie image)
- Install 10.3.0 fastboot ROM again to start over, boot it once. Just to make sure everything is good.
- Reboot to fastboot.
- Boot the Q image of TWRP.
- Run the TWRP installer, reboot to recovery
- You backed everything up right?
- Factory reset (This is the slider at the bottom in the wipe menu).
- Format data. (This is the button that says Format data in the wipe menu)
- Do NOT wipe cache, do not Wipe system, do NOT Wipe Dalvik / ART, do not add anything else, Just Factory Reset and Format Data. After doing those two Reboot to Recovery one more time. You must do this after formatting data.
- Now transfer Lineage and TWRP to your phone, Windows / Linux should see TWRP fine as a media device when plugged in.
- Install Lineage
- Run the TWRP Installer.
- Reboot to Recovery.
- Install Lineage (You need Lineage on both slots, so yes run it again)
- Run the TWRP Installer (yes again).
- Reboot to Recovery.
- Install Gapps if you want them.
- Install Magisk 20.3 if you use Magisk. I used 20.3 it works fine. (20.4 also fine) Do not install modules or other add ons at this point. Boot once and go through the setup and everything, then install your add-ons.
- Be aware the phone will restart once, then Lineage will start up and all will be good.
From that point on updating should just be like normal :
- Reboot to recovery
- Flash Lineage.
- Flash TWRP Installer
- Reboot to Recovery
- Flash Gapps. (Assuming you use them, if you installed them once you must continue to install them or do a clean install)
- Flash Magisk. (If you use it)
- Reboot to system.
- No loss of data, or anything.
- No need to flash anything twice etc.
I've posted similar instructions here. It was just for LOS 16, same thing essentially though.

OhioYJ said:
I've updated these instructions here, they are the same, just added to them really.
This is how I install Lineage 17. (If you are doing 16, replace 10.3.0 with 9.0.17, and the Q image of TWRP with the Pie image)
- Install 10.3.0 fastboot ROM again to start over, boot it once. Just to make sure everything is good.
- Reboot to fastboot.
- Boot the Q image of TWRP.
- Run the TWRP installer, reboot to recovery
- You backed everything up right?
- Factory reset (This is the slider at the bottom in the wipe menu).
- Format data. (This is the button that says Format data in the wipe menu)
- Do NOT wipe cache, do not Wipe system, do NOT Wipe Dalvik / ART, do not add anything else, Just Factory Reset and Format Data. After doing those two Reboot to Recovery one more time. You must do this after formatting data.
- Now transfer Lineage and TWRP to your phone, Windows / Linux should see TWRP fine as a media device when plugged in.
- Install Lineage
- Run the TWRP Installer.
- Reboot to Recovery.
- Install Lineage (You need Lineage on both slots, so yes run it again)
- Run the TWRP Installer (yes again).
- Reboot to Recovery.
- Install Gapps if you want them.
- Install Magisk 20.3 if you use Magisk. I used 20.3 it works fine. (20.4 also fine) Do not install modules or other add ons at this point. Boot once and go through the setup and everything, then install your add-ons.
- Be aware the phone will restart once, then Lineage will start up and all will be good.
From that point on updating should just be like normal :
- Reboot to recovery
- Flash Lineage.
- Flash TWRP Installer
- Reboot to Recovery
- Flash Gapps. (Assuming you use them, if you installed them once you must continue to install them or do a clean install)
- Flash Magisk. (If you use it)
- Reboot to system.
- No loss of data, or anything.
- No need to flash anything twice etc.
I've posted similar instructions here. It was just for LOS 16, same thing essentially though.
Click to expand...
Click to collapse
Sir, apology for being an old noob, I am on OOS 10.3.2 TWRP 3.3.1-32 can I follow the above guide? If Yes,
Why aren't we using the "Lineage Recovery" provided in "Lineage OS Downloads" page?? If we use it, will the above instructions change ? What are the cons of using it?
Sorry again for asking!! Can you please share me the Link to Open Gapps which Will be suitable in my scenario ?

Advised Sloth said:
Sir, apology for being an old noob, I am on OOS 10.3.2 TWRP 3.3.1-32 can I follow the above guide? If Yes,
Why aren't we using the "Lineage Recovery" provided in "Lineage OS Downloads" page?? If we use it, will the above instructions change ? What are the cons of using it?
Sorry again for asking!! Can you please share me the Link to Open Gapps which Will be suitable in my scenario ?
Click to expand...
Click to collapse
Historically Lineage / CM recovery was hit or miss, or TWRP or other recoverys worked better. To be fair I haven't even tried the Lineage recovery. So maybe that is no longer true? Right now, I know TWRP works. The updated instructions link up there has links in it, FYI, link OpenGapps. OpenGapps can be found here. You will be using Arm64, Android 10 obviously.
Since you are already on 10.3.2 (I assume you were on 10.3.1 before) you should be good to skip the step about fastboot ROM or install OOS, and you already have TWRP., so you should be able to go right on to backing everything up, wiping everything, and installing Lineage. (So you can skip the first few steps)
Anymore questions feel free to ask.

OhioYJ said:
Historically Lineage / CM recovery was hit or miss, or TWRP or other recoverys worked better. To be fair I haven't even tried the Lineage recovery. So maybe that is no longer true? Right now, I know TWRP works. The updated instructions link up there has links in it, FYI, link OpenGapps. OpenGapps can be found here. You will be using Arm64, Android 10 obviously.
Since you are already on 10.3.2 (I assume you were on 10.3.1 before) you should be good to skip the step about fastboot ROM or install OOS, and you already have TWRP., so you should be able to go right on to backing everything up, wiping everything, and installing Lineage. (So you can skip the first few steps)
Anymore questions feel free to ask.
Click to expand...
Click to collapse
First of all, thank you very much for your time and explanation.
Sir, so i will proceed as follows:
* Boot into TWRP Recovery
* Perform "swipe to factory reset" & "swipe to wipe data"
* Reboot to TWRP recovery again
* Flash LOS 17.1 on slot A
* Reboot to TWRP recovery again
* Flash LOS 17.1 on slot B
* Reboot to system
Sir, please check are my steps correct? If not,
From which step( steps mentioned in your guide) should i start?
Last query is, which GApps zip will be best for me, micro/nano/pico/tv stock, If i want max coverage of google?
Very sorry for knocking you repeatedly!!!

Advised Sloth said:
First of all, thank you very much for your time and explanation.
Last query is, which GApps zip will be best for me, micro/nano/pico/tv stock, If i want max coverage of google?
Click to expand...
Click to collapse
Your starting point is correct. However make sure you don't miss the re-install TWRP after flashing Lineage each time, and the second time you need to flash Gapps before you reboot to system.
Personally I always do Nano. Anything else you need (that would be included in Micro) can be installed from the Play store. Nano at least includes all the things that can't be installed from the play store.
Pico has the least in it. TV is for TV devices. On OpenGapps there is a box next to each package you can click and it will tell you exactly what is in each package.

OhioYJ said:
I've updated these instructions here, they are the same, just added to them really.
This is how I install Lineage 17. (If you are doing 16, replace 10.3.0 with 9.0.17, and the Q image of TWRP with the Pie image)
- Install 10.3.0 fastboot ROM again to start over, boot it once. Just to make sure everything is good.
- Reboot to fastboot.
- Boot the Q image of TWRP.
- Run the TWRP installer, reboot to recovery
- You backed everything up right?
- Factory reset (This is the slider at the bottom in the wipe menu).
- Format data. (This is the button that says Format data in the wipe menu)
- Do NOT wipe cache, do not Wipe system, do NOT Wipe Dalvik / ART, do not add anything else, Just Factory Reset and Format Data. After doing those two Reboot to Recovery one more time. You must do this after formatting data.
- Now transfer Lineage and TWRP to your phone, Windows / Linux should see TWRP fine as a media device when plugged in.
- Install Lineage
- Run the TWRP Installer.
- Reboot to Recovery.
- Install Lineage (You need Lineage on both slots, so yes run it again)
- Run the TWRP Installer (yes again).
- Reboot to Recovery.
- Install Gapps if you want them.
- Install Magisk 20.3 if you use Magisk. I used 20.3 it works fine. (20.4 also fine) Do not install modules or other add ons at this point. Boot once and go through the setup and everything, then install your add-ons.
- Be aware the phone will restart once, then Lineage will start up and all will be good.
From that point on updating should just be like normal :
- Reboot to recovery
- Flash Lineage.
- Flash TWRP Installer
- Reboot to Recovery
- Flash Gapps. (Assuming you use them, if you installed them once you must continue to install them or do a clean install)
- Flash Magisk. (If you use it)
- Reboot to system.
- No loss of data, or anything.
- No need to flash anything twice etc.
I've posted similar instructions here. It was just for LOS 16, same thing essentially though.
Click to expand...
Click to collapse
Sorry for the necropost, but this also works for TWRP 3.6 and Lineage 18.1. I initially had a problem with the default TWRP for my 6t. During the initial TWRP fastboot the version on their site caused a firmware error which I could just barely get out of, but it screwed up the system boot process in some subtle way that even the fixed version of TWRP (found on this site) couldn't solve.
After trying your instructions above, it didn't work the first time because of the screwed up system boot. It just kept trying to boot to recovery. I suspected a firmware error and was almost going to do an mcmdownload soft-brick rescue. I tried one last thing, using the TWRP on the system to sideload the stock ROM. That worked and patched up the system boot process. Once I booted and ran through some basic initialization to make sure developer options were properly set I followed the above instructions and it worked nearly flawlessly.
One strange thing. After I installed Lineage 18.1 and TWRP to both partitions (as well as Gapps / magisk), it rebooted to system and almost booted without incident -- except a large circular logo popped up that said 100% and stopped. I figured that that meant someting completed properly, so I powered off, waited 10 seconds, powered on and then the Lineage green system initialization spinner came up for a few minutes and it went through the user initialization sequence.
Thanks. I almost gave up and bought a new phone.

OhioYJ said:
I've updated these instructions here, they are the same, just added to them really.
This is how I install Lineage 17. (If you are doing 16, replace 10.3.0 with 9.0.17, and the Q image of TWRP with the Pie image)
- Install 10.3.0 fastboot ROM again to start over, boot it once. Just to make sure everything is good.
- Reboot to fastboot.
- Boot the Q image of TWRP.
- Run the TWRP installer, reboot to recovery
- You backed everything up right?
- Factory reset (This is the slider at the bottom in the wipe menu).
- Format data. (This is the button that says Format data in the wipe menu)
- Do NOT wipe cache, do not Wipe system, do NOT Wipe Dalvik / ART, do not add anything else, Just Factory Reset and Format Data. After doing those two Reboot to Recovery one more time. You must do this after formatting data.
- Now transfer Lineage and TWRP to your phone, Windows / Linux should see TWRP fine as a media device when plugged in.
- Install Lineage
- Run the TWRP Installer.
- Reboot to Recovery.
- Install Lineage (You need Lineage on both slots, so yes run it again)
- Run the TWRP Installer (yes again).
- Reboot to Recovery.
- Install Gapps if you want them.
- Install Magisk 20.3 if you use Magisk. I used 20.3 it works fine. (20.4 also fine) Do not install modules or other add ons at this point. Boot once and go through the setup and everything, then install your add-ons.
- Be aware the phone will restart once, then Lineage will start up and all will be good.
From that point on updating should just be like normal :
- Reboot to recovery
- Flash Lineage.
- Flash TWRP Installer
- Reboot to Recovery
- Flash Gapps. (Assuming you use them, if you installed them once you must continue to install them or do a clean install)
- Flash Magisk. (If you use it)
- Reboot to system.
- No loss of data, or anything.
- No need to flash anything twice etc.
I've posted similar instructions here. It was just for LOS 16, same thing essentially though.
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OhioYJ, these are great instructions but it initially left me with questions about how that procedures would create duplicate installs on slot A and B. The answer is of course that the Lineage installer for the 6t knows about the dual slot setup and always writes to the inactive slot. Booting into recovery activates the inactive slot so that installing again after that installs to the other slot and now you have Lineage on both slots. The installer for TWRP always installs to both slots and is needed because Lineage always installs its recovery handler and you don't want that so you overwrite.
PS: TWRP has an option for installing itself after installing the requested package. Would that be just as good as installing the TWRP zip?
PPS: I had to do an 'adb push' of the Lineage and TWRP zips to sdcard for the installs. Unfortunately installing and slot switching makes the sdcard unavailable so you have to push the zips again. Is there somewhere I can write them to that I don't lose access to after a boot to recovery?