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flashing custom rom on A/B device

Why,in custom ROMs section on 6t forum,every one of custom rom developer in his OP states DIFFERENT "Flashing instructions"?
Not a single rom dev,in his OP have same flashing instructions as some other dev! As I read more,it looks like half of them are wrong instructions,or that they don't have this device,or they don't know.
- flashing on both slots a&b?
flash OOS rom,them twrp.zip,reboot to TWRP (to any of slots),and internal will be encrypted and unreadable.Theres no way to flash on both slots in one take in TWRP or in two takes in row(with in TWRP,reboot to TWRP different slot).There's need for at least one full boot to Operating System,then back to TWRP,and internal will be visible and decrypt ed.
Many custom ROMs need OOS on both slots to be able to make them run,but this looks like nonsense to me.
- changing slots in TWRP?
let's say you flash magisk while in slot A,go to "reboot" and change slot to B, but dont reboot to TWRP.Now flash magisk.it will flash on same slot as first time,there was no slot changing.
- delete wipe "system" in TWRP,or worse "factory reset"?
it's mistake that costs me a lot of time,Ill never do it again.As all custom ROMs now have script that wipes all unnecessary files,there's no need to wipe system and screw your phone for few hours until you fix it.For me,a big No No.
best way of flashing custom os over OOS?
for me,I go into TWRP,flash custom rom,flash TWRP zip,then I reboot into TWRP and flash gapps and magisk.if internal is crypted and I can't flash gapps and magisk,I do a boot into rom,and back to TWRP to finish my flashing.wiola,it boots and works,clean rom and all is fine.
Flash back to OOS?I just go into TWRP,flash OOS ,flash twrp.zip,reboot to twrp and flash magisk.if internal is crypted,I boot into OOS,them back to TWRP,and flash everything else what I need(like magisk and kernel)
a/b devices are nothing new,but it looks to me Like on 6t is all overcomplicated.
So,tell me how you guys do it and what are yours ways of doing it right?

shawek said:
Why,in custom ROMs section on 6t forum,every one of custom rom developer in his OP states DIFFERENT "Flashing instructions"?
Not a single rom dev,in his OP have same flashing instructions as some other dev! As I read more,it looks like half of them are wrong instructions,or that they don't have this device,or they don't know.
- flashing on both slots a&b?
flash OOS rom,them twrp.zip,reboot to TWRP (to any of slots),and internal will be encrypted and unreadable.Theres no way to flash on both slots in one take in TWRP or in two takes in row(with in TWRP,reboot to TWRP different slot).There's need for at least one full boot to Operating System,then back to TWRP,and internal will be visible and decrypt ed.
Many custom ROMs need OOS on both slots to be able to make them run,but this looks like nonsense to me.
- changing slots in TWRP?
let's say you flash magisk while in slot A,go to "reboot" and change slot to B, but dont reboot to TWRP.Now flash magisk.it will flash on same slot as first time,there was no slot changing.
- delete wipe "system" in TWRP,or worse "factory reset"?
it's mistake that costs me a lot of time,Ill never do it again.As all custom ROMs now have script that wipes all unnecessary files,there's no need to wipe system and screw your phone for few hours until you fix it.For me,a big No No.
best way of flashing custom os over OOS?
for me,I go into TWRP,flash custom rom,flash TWRP zip,then I reboot into TWRP and flash gapps and magisk.if internal is crypted and I can't flash gapps and magisk,I do a boot into rom,and back to TWRP to finish my flashing.wiola,it boots and works,clean rom and all is fine.
Flash back to OOS?I just go into TWRP,flash OOS ,flash twrp.zip,reboot to twrp and flash magisk.if internal is crypted,I boot into OOS,them back to TWRP,and flash everything else what I need(like magisk and kernel)
a/b devices are nothing new,but it looks to me Like on 6t is all overcomplicated.
So,tell me how you guys do it and what are yours ways of doing it right?
Click to expand...
Click to collapse
I agree with you!!! This is a mess

even though I have flashed thousands of roms over the years, since I got rid of my Nexus 6, I havent had a phone that I could flash roms on, so, after dumping my Note 8 for this great phone, I was very hesitant to flash a custom rom, for all the reasons you have mentioned..
So, my question is, can you flash ANY of these custom roms by using the clear method that you mentioned in the OP?
If on one of the beta releases, is the procedure the same as I am showing below, or, do you always have to first return to stock OOS?
In my years of flashing dozens of phones, you never had to go back to "stock" if you wiped everything before flashing, but, it seems like on several of these roms, you are instructed to first return to "stock", THEN flash the new custom rom...
Plus, some roms say to wipe everything before you flash, and others say not to wipe system, or not to wipe data...
Unless I am nuts, I always thought that you wipe everything before converting to a totally new rom, but, maybe I am wrong here too..
"for me,I go into TWRP,flash custom rom,flash TWRP zip,then I reboot into TWRP and flash gapps and magisk.if internal is crypted and I can't flash gapps and magisk,I do a boot into rom,and back to TWRP to finish my flashing.wiola,it boots and works,clean rom and all is fine."
These instructions seem pretty clear and concise, hopefully, they are correct, and we can just use this exact method and be done with it!
No mention of wiping in your directions...what do YOU wipe before flashing a new custom rom?
Hopefully, this gets cleared up once and for all, and we can ask the MODS to make a sticky of the ACTUAL CORRECT INSTRUCTIONS>>
thanks

wase4711 said:
"for me,I go into TWRP,flash custom rom,flash TWRP zip,then I reboot into TWRP and flash gapps and magisk.if internal is crypted and I can't flash gapps and magisk,I do a boot into rom,and back to TWRP to finish my flashing.wiola,it boots and works,clean rom and all is fine."
These instructions seem pretty clear and concise, hopefully, they are correct, and we can just use this exact method and be done with it!
No mention of wiping in your directions...what do YOU wipe before flashing a new custom rom?
Hopefully, this gets cleared up once and for all, and we can ask the MODS to make a sticky of the ACTUAL CORRECT INSTRUCTIONS>>
thanks
Click to expand...
Click to collapse
-if on custom rom,probably it's good to first go to stock OOS and then to another custom rom.but this is also strange to me,as I don't understand what are benefits of this.i also read this,Google heh.i tried going from AOSCP to PixelEcpirince without flashing OOS in-between process,all was fine.
-I haven't been on Beta OOS yet,only stable.But that thing bout "before flashing custom rom,flash stable OOS even if your on Beta OOS" is also a big question to me.they are practically the same,both are latest OOS,one maybe more stable them other,but this also can be discussed hehe
-i don't wipe anything!! when my custom rom boots,I go into it's settings, without setting my Google account and other stuff, and I do "factory reset"( not in TWRP,in custom rom's settings!).Phone reboots,and all is fine,clean beginning,TWRP works,root works.About unwantedFolders in internal storage,I delete them manualy.

Only thing in my experience to wipe in TWRP is DATA,but this is also questionable,as I run into problems also doing data wipe I TWRP.
Now ROMs(maybe only for a/b devices) have scripts that wipe previous System during flashing new rom,so we don't have to do a Clean Flash anymore.
I'm also confused,more I read,less I understand ?

I like the idea of wiping via factory reset, once the rom boots, but, if it does NOT boot, then you wouldnt be able to do it that way..
I guess flashing an OOS based rom over an OOS based rom would always allow you to boot, if done right..
But, roms like RR, Carbon, AICP, and a couple others that have shown up here recently were never really OOS based roms, but AOSP based, at least I thought so..
the more I think about this, the more confusing it seems to get..

wase4711 said:
I like the idea of wiping via factory reset, once the rom boots, but, if it does NOT boot, then you wouldnt be able to do it that way..
I guess flashing an OOS based rom over an OOS based rom would always allow you to boot, if done right..
But, roms like RR, Carbon, AICP, and a couple others that have shown up here recently were never really OOS based roms, but AOSP based, at least I thought so..
the more I think about this, the more confusing it seems to get..
Click to expand...
Click to collapse
This is from the pixel 2 xl forum another a/b device
First time installing Pixel Dust ROM, or coming from another ROM:
As mentioned above, you are required to flash stock ROM before installing this custom ROM.
1. Flashing Stock ROM:
Follow these instructions: https://developers.google.com/android/images#taimen
2. Flashing PixelDust ROM:
Reboot to twrp
Wipe Dalvik cache and Data partitions
Flash ROM
Flash twrp zip
Reboot to System and enjoy the Pixel Dust Goodness!
Flashing Magisk:
You cannot flash Magisk during the initial install. You must boot into PixelDust ROM at least once!
Reboot to Recovery
Flash Magisk-v17.x.zip
Reboot to System

shawek said:
Why,in custom ROMs section on 6t forum,every one of custom rom developer in his OP states DIFFERENT "Flashing instructions"?
Not a single rom dev,in his OP have same flashing instructions as some other dev! As I read more,it looks like half of them are wrong instructions,or that they don't have this device,or they don't know.
- flashing on both slots a&b?
flash OOS rom,them twrp.zip,reboot to TWRP (to any of slots),and internal will be encrypted and unreadable.Theres no way to flash on both slots in one take in TWRP or in two takes in row(with in TWRP,reboot to TWRP different slot).There's need for at least one full boot to Operating System,then back to TWRP,and internal will be visible and decrypt ed.
Many custom ROMs need OOS on both slots to be able to make them run,but this looks like nonsense to me.
- changing slots in TWRP?
let's say you flash magisk while in slot A,go to "reboot" and change slot to B, but dont reboot to TWRP.Now flash magisk.it will flash on same slot as first time,there was no slot changing.
- delete wipe "system" in TWRP,or worse "factory reset"?
it's mistake that costs me a lot of time,Ill never do it again.As all custom ROMs now have script that wipes all unnecessary files,there's no need to wipe system and screw your phone for few hours until you fix it.For me,a big No No.
best way of flashing custom os over OOS?
for me,I go into TWRP,flash custom rom,flash TWRP zip,then I reboot into TWRP and flash gapps and magisk.if internal is crypted and I can't flash gapps and magisk,I do a boot into rom,and back to TWRP to finish my flashing.wiola,it boots and works,clean rom and all is fine.
Flash back to OOS?I just go into TWRP,flash OOS ,flash twrp.zip,reboot to twrp and flash magisk.if internal is crypted,I boot into OOS,them back to TWRP,and flash everything else what I need(like magisk and kernel)
a/b devices are nothing new,but it looks to me Like on 6t is all overcomplicated.
So,tell me how you guys do it and what are yours ways of doing it right?
Click to expand...
Click to collapse
You make it overcomplicated.
To flash both slots you only need to do a complete reboot to make sure the OS is not hosed.
You do that so if it is you can use the other slot. This is not necessary.
You flash in TWRP, change the slot and reboot into TWRP and flash the other slot.
It could be easier if TWRP allowed flashing on the inactive slot.
But, even if you are rooted and want to upgrade it is suggested to upgrade both slots.
I think it's just a minor pain. There are bigger problems.

tech_head said:
You make it overcomplicated.
To flash both slots you only need to do a complete reboot to make sure the OS is not hosed.
You do that so if it is you can use the other slot. This is not necessary.
You flash in TWRP, change the slot and reboot into TWRP and flash the other slot.
It could be easier if TWRP allowed flashing on the inactive slot.
But, even if you are rooted and want to upgrade it is suggested to upgrade both slots.
I think it's just a minor pain. There are bigger problems.
Click to expand...
Click to collapse
it's not a minor pain if most of time that I go to flash custom rom,I lost all my 60-80gigs of internal data, cuz of failed decryption,or failed rom flash,or failed TWRP flash.There were times when I did Factory reset in TWRP,flashed OOS,flashed TWRP.zip,did reboot to recovery,and I lost recovery.I was left with bootloader (fastboot) and had to fastbooting OOS few times(which led to full wipe of internal storage).OOS wasn't even flashed,or TWRP wanst even flashed.And I just followed instructions.
this are the things that I'm talking about.Even if I follow instructions, instructions are not detailed.
now I probably know how to do it right,,but still...I learned it hard way,and still learning
thanks for your opinion and answer:good:

shawek said:
it's not a minor pain if most of time that I go to flash custom rom,I lost all my 60-80gigs of internal data, cuz of failed decryption,or failed rom flash,or failed TWRP flash.There were times when I did Factory reset in TWRP,flashed OOS,flashed TWRP.zip,did reboot to recovery,and I lost recovery.I was left with bootloader (fastboot) and had to fastbooting OOS few times(which led to full wipe of internal storage).OOS wasn't even flashed,or TWRP wanst even flashed.And I just followed instructions.
this are the things that I'm talking about.Even if I follow instructions, instructions are not detailed.
now I probably know how to do it right,,but still...I learned it hard way,and still learning
thanks for your opinion and answer:good:
Click to expand...
Click to collapse
I understand now.
The instructions are not clear for most of this stuff and you can screw up.
If something fails to flash, there are very few reasons to ever completely wipe. Even a factory reset does not require a complete wipe of data.
I would suggest at all times keeping a boot image of the current OS you are using.
I would also suggest keeping a TWRP.img on your computer. You can always boot from a TWRP image even if it's not the one you want to install.
That will at least get decryption and the ability to flash.
I don't flash custom ROMs, because the stock one with root does what I need. Also the fingerprint sensor is not guaranteed under custom ROMs and I need that to work.

no verify opt on most after data wipe or that brands version of it, then reboot to twrp verify is still not there because twrp will say no os installed the avb changed things every phone is different depending on their security Samsung for one

Try this guide. Read the first paragraph if you have problems with decryption.

Boot twrp
Wipe dalvik and data
Flash rom+twrp
Reboot SYSTEM!
Boot back to recovery
Factory reset
Flash gapps+magisk
Reboot and done
No data loss or PC needed...

So here's some food for thought. I read somewhere that when you install a ROM zip via TWRP it actually Installs to the Inactive Slot. And when you reboot to TWRP after reflashing the Installer it Switches Slots and then you can Flash GAPPS etc. But what if someone were to flash the ROM twice ; once to each slot? Would be noice if We can use this to Multi-Boot Two ROMs at once....

Mannan Qamar said:
So here's some food for thought. I read somewhere that when you install a ROM zip via TWRP it actually Installs to the Inactive Slot. And when you reboot to TWRP after reflashing the Installer it Switches Slots and then you can Flash GAPPS etc. But what if someone were to flash the ROM twice ; once to each slot? Would be noice if We can use this to Multi-Boot Two ROMs at once....
Click to expand...
Click to collapse
I think that question was asked in one of the threads in here "can use this to Multi-Boot Two ROMs at once" and I don't think it's possible. I'm sorry I don't remember the thread it was in. You might try Google.

It's wise to do the oos in both slots which you can switch slots without rebooting fyi because when you flash a custom ROM no matter if you switch back to a it'll flash magisk and probably gapps in the inactive slot. If you try to return the custom ROM to slot a after it flashes it will say insufficient room for gapps and such. So to me it seems this makes it a clean slate so it can flash to inactive slot. Hope that clears up why they encourage the double oos flash

Everyone, I think you have almost helped me figure out how I screwed up my 6T. I made a post needing help but this thread I believe is the answer. I wanted to install lineage16 but opted for Resurrection Remix since that dev claimed the fingerprint reader worked. To make a long story short, I flashed the latest .15 OxyOS update first, switched partitions via TWRP and flashed it again, them flashed TWRP and rebooted to recovery. Flashed Remix then TWRP again and rebooted to Remix. Now I have no room for anything in storage although it's only 25% full and my file explorer cannot access any storage not can I update apps through play store or anything. I have the latest OxyOS on my OTG flash drive as well as TWRP and magisk, but every time I find a thread on hope to do an installation, it varies and I keep coming back to this storage issue. Can someone PLEASE link me out tell me where to find the correct process to now start from the beginning and get my phone back working on the OxyOS .15 stock rom? Thank you very much and I'm glad I found this thread because it finally makes sense as to how misinformation is causing many people to have issues.

SuperUnkn0wn0ne said:
Everyone, I think you have almost helped me figure out how I screwed up my 6T. I made a post needing help but this thread I believe is the answer. I wanted to install lineage16 but opted for Resurrection Remix since that dev claimed the fingerprint reader worked. To make a long story short, I flashed the latest .15 OxyOS update first, switched partitions via TWRP and flashed it again, them flashed TWRP and rebooted to recovery. Flashed Remix then TWRP again and rebooted to Remix. Now I have no room for anything in storage although it's only 25% full and my file explorer cannot access any storage not can I update apps through play store or anything. I have the latest OxyOS on my OTG flash drive as well as TWRP and magisk, but every time I find a thread on hope to do an installation, it varies and I keep coming back to this storage issue. Can someone PLEASE link me out tell me where to find the correct process to now start from the beginning and get my phone back working on the OxyOS .15 stock rom? Thank you very much and I'm glad I found this thread because it finally makes sense as to how misinformation is causing many people to have issues.
Click to expand...
Click to collapse
You may have solved this by now, but I found that using the MSM Download Tool has enabled me to return to stock OxygenOS even after getting stuck in a boot loop. I've not been able to successfully flash RR or LineageOS however, still getting stuck in said boot loop...

What's the REAL method to successfully install a working TWRP, root and custom ROM?

Hi All, I have been reading various threads here and searching on Google for finding a method that truly works for successfully installing a custom ROM, getting TWRP installed and rooting with Magisk. So far, all I have found are numerous and usually contradictory methods and about 7 or 8 different versions of TWRP (so which one is completely stable and working properly?). I have tried several methods over the past two weeks and none of them are working completely.
Sometimes, I'll get a version of TWRP installed, but then trying to reboot to recovery results in a "system has been destroyed" image. Or I'll succeed in getting a custom ROM installed, but Gapps will fail with error 20 or error 70 or there's not enough space on the system partition (and I'm just trying to install the Pico version). Even I double check that the Gapps version matches the ROM version I've used, but still get an error 20 displayed.
From what I had read on numerous threads, it seemed like CosmicDans TWRP would be the one I should go with. I downloaded both of his files (the fastboot image and the zipped installer) and fastboot his "boot-recovery.img" that was specifically for fastboot only and from that recovery, I installed his "TWRP-Installer-3.2.1-with-Tissot-Manager-2.5.zip". Everything appeared as if successfully installed as per the logs, but immediately upon attempting to reboot to recovery, I get the "system has been destroyed" image.
What I want to do is:
Get a working custom ROM (preferably Pie) installed
Install Gapps
Install a working TWRP (that will not display "system has been destroyed" whenever trying to boot to recovery)
Finally, install Magisk and root my phone
Can anyone suggest a site or link or a post somewhere that would explain everything correctly and is actually working? This has been a very frustrating experience. I'm almost sorry that I even bought the Mi A1. Never had any problems installing custom ROMs or rooting the OnePlus devices. All I'm left with currently is an expensive paperweight.
Thanks so much!
Cheers

From your description, I'm certain that you do this on a Pie stock rom right? the installer never work on Pie stock and will cause system destroy. Just hotboot TWRP. And for the Gapps, I think it's due to the time you install it. From my experience, install Gapps after rom and before Magisk usually work. Install after magisk or custom kernel will somehow cause the same issue that you described.
Oh, in case you want to install LineageOS, you have to come to the LOS16 thread and download the TWRP from there, it's the only TWRP that can install LOS16.

Never_Sm1le said:
From your description, I'm certain that you do this on a Pie stock rom right? the installer never work on Pie stock and will cause system destroy. Just hotboot TWRP. And for the Gapps, I think it's due to the time you install it. From my experience, install Gapps after rom and before Magisk usually work. Install after magisk or custom kernel will somehow cause the same issue that you described.
Oh, in case you want to install LineageOS, you have to come to the LOS16 thread and download the TWRP from there, it's the only TWRP that can install LOS16.
Click to expand...
Click to collapse
Thank you for your reply. When I first started the process to change to a custom ROM, I was on stock Pie. But one of the times I was wiping the device after one more problem, I accidentally also wiped Internal Storage as well. I didn't have much there since I had already backed some things up in advance. Now it's virtually empty. The steps I take are:
1. Hotboot TWRP
2. Install Custom ROM
3. Hotboot TWRP again
4. Install Gapps
This is where I usually have some problem. It's the process of installing Gapps that creates some error.
I also did attempt to install LineageOS 16 using the TWRP recovery that was linked in the post. Follow the instructions precisely I believe and now when it's time to install Gapps, I get error 64. I can't understand why. I am attempting to install "open_gapps-arm64-9.0-nano". This should be compatible with the Mi A1 with LineageOS 16 from what I am able to tell.
No matter what TWRP version I use, no matter what custom ROM I try, no matter what steps I take, there is always some issue that prevents me from completing any installation. But the abundance of so many conflicting posts don't help either. One post will state to use a specific TWRP and certain steps; another post will suggest completely different steps using another TWRP; and yet another post will provide different steps still. In some instances, there will be steps listed in the script on the phone regarding the next steps after the ROM installation that are completely different then the steps provided in the post for that ROM in the forum.
It would just be tremendously helpful to get some instructions that actually do work. As of now, I'm about ready to dump this phone in the trash bin. It's horrible. I can't even tell if it might be decent eventually since I never can get anything installed.
Thanks again for your reply Never_Sm1le.
Cheers.

There is no permanent TWRP install for android 9 on MiA1 as far as i know.
Hotboot works just perfect.

Brianne8 said:
Thank you for your reply. When I first started the process to change to a custom ROM, I was on stock Pie. But one of the times I was wiping the device after one more problem, I accidentally also wiped Internal Storage as well. I didn't have much there since I had already backed some things up in advance. Now it's virtually empty. The steps I take are:
1. Hotboot TWRP
2. Install Custom ROM
3. Hotboot TWRP again
4. Install Gapps
This is where I usually have some problem. It's the process of installing Gapps that creates some error.
I also did attempt to install LineageOS 16 using the TWRP recovery that was linked in the post. Follow the instructions precisely I believe and now when it's time to install Gapps, I get error 64. I can't understand why. I am attempting to install "open_gapps-arm64-9.0-nano". This should be compatible with the Mi A1 with LineageOS 16 from what I am able to tell.
No matter what TWRP version I use, no matter what custom ROM I try, no matter what steps I take, there is always some issue that prevents me from completing any installation. But the abundance of so many conflicting posts don't help either. One post will state to use a specific TWRP and certain steps; another post will suggest completely different steps using another TWRP; and yet another post will provide different steps still. In some instances, there will be steps listed in the script on the phone regarding the next steps after the ROM installation that are completely different then the steps provided in the post for that ROM in the forum.
It would just be tremendously helpful to get some instructions that actually do work. As of now, I'm about ready to dump this phone in the trash bin. It's horrible. I can't even tell if it might be decent eventually since I never can get anything installed.
Thanks again for your reply Never_Sm1le.
Cheers.
Click to expand...
Click to collapse
Your reply makes me want to stay on LOS 15.1 even more. So many weird problems happen in LOS 16

I followed all the instructions of Resurrection Remix and TWRP is installed and magisk works perfect.

Hello friend, I am currently on Lineage OS 16.0 with Magisk, Opengapps and TWRP installed. I can boot to recovery with no problems at all; in fact, I used the flashed TWRP to install Magisk.
Here are the steps I took:
Download the TWRP boot img and TWRP installer by CosmicDan (Link below)
Copy the custom rom ZIP, TWRP installer, Magisk installer and Gapps into your SD card
Reboot your device to bootloader
Boot into TWRP using
Code:
fastboot boot boot-recovery.img
do NOT flash via fastboot
Go to Wipe>Advanced Wipe and wipe System, Dalvik, Data, Internal Storage
Press the home button and proceed to flashing the custom rom ZIP
After flashing, reboot to BOOTLOADER then do step 4 again
Flash Gapps, TWRP Installer, then Magisk Installer. You should flash TWRP first before Magisk
Reboot to system and you're good to go
Note that if you are installing Lineage OS and wish to receive nightly OTA updates, having an installed TWRP as your recovery might result in a bootloop after updating. Also, if you want to manually flash the nightly update, you need to boot to the TWRP variant of @flex1911 as flashing lineage using other TWRP will result in an error. I suggest not installing TWRP when using Lineage OS.
(Source: [ROM][OFFICIAL] LineageOS 16.0 for Xiaomi Mi A1)
Regarding your problem with flashing, try to check which slot you are currently in by going to TWRP>Reboot. Keep in mind that when you install a rom, it will always be installed to the inactive slot. For example if you are in slot A, your rom will be installed in slot B. After rebooting, your current active slot will be where the rom is installed. When installing Gapps or any addons, check the slot first. However, when flashing TWRP installer, it will patch both boot_a and boot_b and this is the reason why you need to install twrp first before magisk as TWRP also modifies the boot image.
Download:
Bootable TWRP
TWRP Installer
(Both files by @CosmicDan)
Cheers mate!

rexendz said:
Here are the steps I took:
Download the TWRP boot img and TWRP installer by CosmicDan (Link below)
Copy the custom rom ZIP, TWRP installer, Magisk installer and Gapps into your SD card
Reboot your device to bootloader
Boot into TWRP using
Code:
fastboot boot boot-recovery.img
do NOT flash via fastboot
Go to Wipe>Advanced Wipe and wipe System, Dalvik, Data, Internal Storage
Press the home button and proceed to flashing the custom rom ZIP
After flashing, reboot to BOOTLOADER then do step 4 again
Flash Gapps, TWRP Installer, then Magisk Installer. You should flash TWRP first before Magisk
Reboot to system and you're good to go
Click to expand...
Click to collapse
Thanks for the lengthy reply. However, those steps do not work as you have described. Since, if I wipe Internal Storage (as per your step 5), I just deleted all the files I copied previously in Step 2. What I did, was wipe everything, *then* copied all the files and tried to install. As soon as it try to install Gapps, I get Error 64 again. I am absolutely using "open_gapps-arm64-9.0-nano" and it always fails. I have attempted 11 or 12 times already, using different slots, using different dates of "open_gapps-arm64-9.0-nano" and ALWAYS Error 64. I don't know any other version of Gapps I should be trying. The arm64 versions never will work for me.
I give up. I'll just have to stick with stock ROM. No custom ROMs will work for me no matter which one I use or which version of TWRP I use. I already wasted too much of my life with this garbage phone.

ccalixtro said:
I followed all the instructions of Resurrection Remix and TWRP is installed and magisk works perfect.
Click to expand...
Click to collapse
Hi,
Which version of TWRP did you use? There's too many. I don't know which one is considered to be the right one.

Brianne8 said:
Thanks for the lengthy reply. However, those steps do not work as you have described. Since, if I wipe Internal Storage (as per your step 5), I just deleted all the files I copied previously in Step 2. What I did, was wipe everything, *then* copied all the files and tried to install. As soon as it try to install Gapps, I get Error 64 again. I am absolutely using "open_gapps-arm64-9.0-nano" and it always fails. I have attempted 11 or 12 times already, using different slots, using different dates of "open_gapps-arm64-9.0-nano" and ALWAYS Error 64. I don't know any other version of Gapps I should be trying. The arm64 versions never will work for me.
I give up. I'll just have to stick with stock ROM. No custom ROMs will work for me no matter which one I use or which version of TWRP I use. I already wasted too much of my life with this garbage phone.
Click to expand...
Click to collapse
Copy the files to your external SD card not internal storage. But if you don't have an ext SD card, don't wipe internal storage.
Also try to check if system is properly mounted when installing gapps.
May I ask what custom rom you are trying to install?
I suggest you try Pixel Experience as it already has a builtin Gapps so you dont have to flash opengapps.

OnePlus 6t Wifi Issue on custom roms

Okay so I've tried Pixel experience, lineage os , omni rom treskmod and couple of other custom android 10 roms, all stable and official and also updated ones, the wifi just simply doesn't work, wifi hotspot won't turn on either. I've tried every solution on the internet. I've even factory reset my phone using msm download tool and no luck(did this countless times).
I'm back in OOS 10.3.2 and there's no issue apparently.
At one point , i flashed a custom rom and the wifi didn't work, so I flashed OOS in the two slots and checked , the wifi works in OOS apparently, and never in custom roms.
Has anyone got this issue before and knows a solution?

How is your installation procedure?

onliner said:
How is your installation procedure?
Click to expand...
Click to collapse
I flash OOS and twrp on both slots, reboot recovery,
And then flash the rom and twrp, reboot recovery,then format data and factory reset, reboot recovery, if needed for some gapps, then reboot system

ivanthomas said:
I flash OOS and twrp on both slots, reboot recovery,
And then flash the rom and twrp, reboot recovery,then format data and factory reset, reboot recovery, if needed for some gapps, then reboot system
Click to expand...
Click to collapse
That's a lot of unnecessary steps. OOS on both slots, reboot to bootloader, boot twrp, format data and flash the custom rom, reboot bootloader, boot twrp and flash gapps, don't install twrp permanently if you are not going to install Magisk.

onliner said:
That's a lot of unnecessary steps. OOS on both slots, reboot to bootloader, boot twrp, format data and flash the custom rom, reboot bootloader, boot twrp and flash gapps, don't install twrp permanently if you are not going to install Magisk.
Click to expand...
Click to collapse
I need magisk too, I usually permanently install twrp
Also you think it's the way I'm installing at fault here? Or the rom? Or is it something wrong with my device?

ivanthomas said:
it's the way I'm installing at fault here?
Click to expand...
Click to collapse
This.
I always install roms with the procedure i said above and have never had any problems.

onliner said:
This.
I always install roms with the procedure i said above and have never had any problems.
Click to expand...
Click to collapse
Alright so got one doubt, I used OOS 10.3.2 to flash, should it be oos 10.0 only?
Thought that didn't make a difference.

I am also facing the same issue. Were you able to find any solution ?

So I found out treskmod omni rom and Paranoid android quartz 2 work perfectly , try those out, it still doesn't solve the problem in the other roms though. So not exactly a solution.

Flash a Custom Rom in 2020?

For the past 24+ hours I've been trying to flash a few custom roms on my UNLOCKED BOOTLOADER OP6T, but the phone TURNS OFF a few seconds after the boot sequence/animation.
I've read about the A/B slots and tried the Roms' flashing instructions, along with a few suggestions from others, but I cannot get any Custom Rom on my phone...
Here are the steps I've taken to flash (a few times I tried different things that I'll put in parenthesis). Is there anything ya'll see that I'm doing wrong?:
Starting from OOS 10.3.2 Fastboot Recovery and all required files on an OTG USB Drive
fastboot to TWRP....img
Confirmed I'm on Slot A
Wipe Data/Dalvik
Install OOS...zip (10.3.2)
Install TWRP...zip (3.3.1.32)
Reboot Recovery
(Format Data)
Confirmed I'm on Slot B
Install OOS...zip (10.3.2)
Install TWRP...zip (3.3.1.32)
Reboot Recovery
Confirmed I'm on Slot A
Install Xtended (v8 4/13)
(Wipe Data/Cache)
Install TWRP...zip (3.3.1.32)
Reboot Recovery
Confirmed I'm on Slot B
Install Xtended (v8 4/13)
(Wipe Data/Cache)
Install TWRP...zip (3.3.1.32)
Reboot Recovery
Confirmed I'm on Slot A
Install GAPPS (Arm64 10.0 Nano)
(Format Data)
Reboot System

My Guide for Lineage, however it will work for most AOSP based ROMs.
I assume you arent manually switching slots. Don't, there is no need, in fact dont worry about it. Slots will switch automatically after flashing a ROM when you reboot recovery. There is no cache partition, stop wiping this, its not doing anything. There are two slots, but only one data partition that is shared, there isnt a reason to keep wiping it.
On most instructions adding or removing steps will make things not work. Unfortunately for this device there is a lot of out dated information and information that just doesnt work. My guide has been tested with 10.3.3, and the latest version of LOS, however if you have a T-Mobile 6T you are on your own. (I have a regular 6T)

OhioYJ said:
My Guide for Lineage, however it will work for most AOSP based ROMs.
I assume you arent manually switching slots. Don't, there is no need, in fact dont worry about it. Slots will switch automatically after flashing a ROM when you reboot recovery. There is no cache partition, stop wiping this, its not doing anything. There are two slots, but only one data partition that is shared, there isnt a reason to keep wiping it.
On most instructions adding or removing steps will make things not work. Unfortunately for this device there is a lot of out dated information and information that just doesnt work. My guide has been tested with 10.3.3, and the latest version of LOS, however if you have a T-Mobile 6T you are on your own. (I have a regular 6T)
Click to expand...
Click to collapse
Thanks for the comment! I just followed your guide, but still seeing the boot animation for a few seconds, then the phone vibrates and turns off.
For kicks, I decided to Format Data and I see the boot animation longer, all the way to the end when it's about to start Android, but then it vibrates and shuts off. Strange.
I'm thinking there is something different about my phone... It's a global, unlocked version and I've rooted/flashed hundreds of roms over the years on various devices, so all of this should be a piece of cake................. Thanks!

oooscasianooo said:
Thanks for the comment! I just followed your guide, but still seeing the boot animation for a few seconds, then the phone vibrates and turns off.
For kicks, I decided to Format Data and I see the boot animation longer, all the way to the end when it's about to start Android, but then it vibrates and shuts off. Strange.
I'm thinking there is something different about my phone... It's a global, unlocked version and I've rooted/flashed hundreds of roms over the years on various devices, so all of this should be a piece of cake................. Thanks!
Click to expand...
Click to collapse
Have you tried without Gapps?

After the shutdown go back to twrp and extract the content of /sys/fs/pstore/* and upload the files here.

onliner said:
After the shutdown go back to twrp and extract the content of /sys/fs/pstore/* and upload the files here.
Click to expand...
Click to collapse
Thanks. I actually gave up and setup stock OOS again, so it took a while to get a TWRP backup, etc. etc.
So after the backup, I installed Xtended + TWRP, reboot to recovery, installed Xtended + TWRP, wiped dalvik, and reboot to system.
Boot animation shut down issue as usual.
Afterwards, I copied the pstore folder (attached zip).
Thanks!

onliner said:
After the shutdown go back to twrp and extract the content of /sys/fs/pstore/* and upload the files here.
Click to expand...
Click to collapse
Anything in the logs I can look for?
This is driving me crazy. I flashed MIUI just fine (because it had the .bat file that does everything for you). Essentially it's doing the same thing as flashing OOS & Rom on A/B, right?
Just tried flashing the newest Xtended Rom (May 11th), same issue. Phone vibrates and completely turns off while the boot animation is running.

OhioYJ said:
My Guide for Lineage, however it will work for most AOSP based ROMs.
I assume you arent manually switching slots. Don't, there is no need, in fact dont worry about it. Slots will switch automatically after flashing a ROM when you reboot recovery. There is no cache partition, stop wiping this, its not doing anything. There are two slots, but only one data partition that is shared, there isnt a reason to keep wiping it.
On most instructions adding or removing steps will make things not work. Unfortunately for this device there is a lot of out dated information and information that just doesnt work. My guide has been tested with 10.3.3, and the latest version of LOS, however if you have a T-Mobile 6T you are on your own. (I have a regular 6T)
Click to expand...
Click to collapse
If you have a TMobile 6t I can confirm I have had to manually change the slots during the flashing process to get custom ROMs installed.

mrmcshagbag said:
If you have a TMobile 6t I can confirm I have had to manually change the slots during the flashing process to get custom ROMs installed.
Click to expand...
Click to collapse
I found out that I do have the T-Mobile version that the seller flashed to International Software haha
When I reboot to recovery, I do see that the slots are being changed though.
Would you mind post the exact steps you took to successfully flash a ROM/GAPPS?

oooscasianooo said:
I found out that I do have the T-Mobile version that the seller flashed to International Software haha
When I reboot to recovery, I do see that the slots are being changed though.
Would you mind post the exact steps you took to successfully flash a ROM/GAPPS?
Click to expand...
Click to collapse
Fastboot boot TWRP Marion version
Flash oos
Flash Marion TWRP zip
Check my slot
Reboot recovery
Changed slot since it didn't change
Reboot recovery
Flash oos
Flash Marion TWRP zip
Changed slot
Reboot recovery
Flash custom rom
Flash Marion TWRP zip
Change slot
Reboot recovery
Flash gapps
Flash magisk 20.4
Reboot to system
Those are the steps I had to take before I finally got a custom rom to work. I tried doing the methods posted which would have probably worked if the slots were changing on there own but they weren't for me.

mrmcshagbag said:
Fastboot boot TWRP Marion version
Flash oos
Flash Marion TWRP zip
Check my slot
Reboot recovery
Changed slot since it didn't change
Reboot recovery
Flash oos
Flash Marion TWRP zip
Changed slot
Reboot recovery
Flash custom rom
Flash Marion TWRP zip
Change slot
Reboot recovery
Flash gapps
Flash magisk 20.4
Reboot to system
Those are the steps I had to take before I finally got a custom rom to work. I tried doing the methods posted which would have probably worked if the slots were changing on there own but they weren't for me.
Click to expand...
Click to collapse
Thanks! Do you mean the "mauronofrio" version?

oooscasianooo said:
Thanks! Do you mean the "mauronofrio" version?
Click to expand...
Click to collapse
Yes couldn't remember the exact name but I knew you would be able to find it haha

mrmcshagbag said:
Yes couldn't remember the exact name but I knew you would be able to find it haha
Click to expand...
Click to collapse
hahaha thanks! I was thinking, "is there a T-Mobile version of TWRP?!" haha!

Slot B always become encrypted when flashing

Hi,
I have not flashed a rom or anything since I replaced my Nexus 6P with my OnePlus 6T about three years ago so this A/B slot thing is all new to me.
I have tried installing two different ROMs, the first one is LineageOS but when I flash it it seems like slot B gets encrypted sence the folders have wierd names and don't contain anything when I rebooting to recovery to flash on slot A.
If I copy slot A to slot B everything looks like normal again. I have followd the guide as I understand it but it wont work so I moved on to try DotOS which have a much more simple guide.
"CLEAN FLASH :
Download the latest build, TWRP, Magisk 21.4 and NikGApps
Reboot to TWRP
Flash OOS, TWRP & Reboot to TWRP This step was fine.
Flash OOS, TWRP & Reboot to TWRP Slot B seems to have become encrypted again.
Flash build, TWRP & Reboot to TWRP
Flash NikGApps (Optional), Magisk (Optional)
Reboot to system"
If OOS stands for OxygenOS, I don't understand what I'm doing wrong. I also tried to remove pin from lockscreen and factory reset after every flash, that didn't wort either.
Thanks in advance!
Sorry if my english is bad, it seems to go downhill at a rapid pace after you graduate...

Lirkaren said:
Hi,
I have not flashed a rom or anything since I replaced my Nexus 6P with my OnePlus 6T about three years ago so this A/B slot thing is all new to me.
I have tried installing two different ROMs, the first one is LineageOS but when I flash it it seems like slot B gets encrypted sence the folders have wierd names and don't contain anything when I rebooting to recovery to flash on slot A.
If I copy slot A to slot B everything looks like normal again. I have followd the guide as I understand it but it wont work so I moved on to try DotOS which have a much more simple guide.
"CLEAN FLASH :
Download the latest build, TWRP, Magisk 21.4 and NikGApps
Reboot to TWRP
Flash OOS, TWRP & Reboot to TWRP This step was fine.
Flash OOS, TWRP & Reboot to TWRP Slot B seems to have become encrypted again.
Flash build, TWRP & Reboot to TWRP
Flash NikGApps (Optional), Magisk (Optional)
Reboot to system"
If OOS stands for OxygenOS, I don't understand what I'm doing wrong. I also tried to remove pin from lockscreen and factory reset after every flash, that didn't wort either.
Thanks in advance!
Sorry if my english is bad, it seems to go downhill at a rapid pace after you graduate...
Click to expand...
Click to collapse
If you are already on OOS and just unlocked bootloader and boot to TWRP you can just skip the flash oos and start from flashing ROM/build
( I'm not responsible for any problems but it's work fine for me)
Or
Flash OOS
Flash ROM/build
Flash Finalize.zip ( use this so you don't have to flash oos multiple times )
Flash twrp.
Flash Gapp (optional )
Format data and reboot to system.

SOK seila said:
If you are already on OOS and just unlocked bootloader and boot to TWRP you can just flash the ROM zip without flashing OOS( I'm not responsible for any problems but it's work fine for me)
Or
Flash OOS
Flash ROM/build
Flash Finalize.zip ( use this so you don't have to flash oos multiple times )
Flash twrp.
Flash Gapp (optional )
Format data and reboot to system.
Click to expand...
Click to collapse
Missed to press format data. This was a day well spent! :'D