Database Users

x720 partial unlocked bootloader? [SOLVED]

So I got my 6GB/64GB x720 yesterday. It had Google Play Store already installed (ordered it from HonorBuy) and asked me to install a 7MB OTA, so it seems it had a recent version of EUI on it. My idea was to put LineageOS 14.1 on it or if it wasn't stable enough for me, at least a debloated and rooted stock. So searched XDA and followed this HowTo. No Errors, flashboot oem device-info said, bootloader unlocked, perfekt. Installed TWRP, downloaded recent LineageOS and followed the guides to flash (wipe, ...). Unfortunately flashing never finished, I always had a full progress-bar and it stayed there without doing anything (ok, the device got hot). Thinking of a broken download, I redownloaded the ROM but same problem. So I started downloading other ROMs from XDA: Resurection Remix and OmniROM. Flashing-process went thru, but couldn't flash gapps and ROMs didn't boot at all. I was always only getting to the LeEco-Bootlogo with the chinese writings. So next thought was, maybe for some reason I can't install Lineage-based ROMs, let's figure out later and get a debloated stock ROM. So I downloaded MAURO V2.2_Free and gave it another try. Looked more promising, as the bootlogo was a little different, no more chinese writing but english. Unfortunately this was all I could see of MAURO as I only got a bootloop... so again reflashed MAURO and this time a single line in TWRP-output came to my eye "boot.img could not be written". I checked flashboot oem device-info after every flash and it always told me, bootloader is unlocked, but there seems to be something else that I'm missing that obviously still keeps the bootloader locked. I wiped the phone several times, even sdcard... nothing helped. The only method that worked for me to get a working rom running was by this guide, manualy flashing every bit of stock ROM with flashboot. With MAURO-ROM, I also tried to flash boot.img manually with flashboot, but that didn't work, either.
Anyone of you experienced the same? What am I missing? Or is this some new protection implemented by LeEco for the most recent devices? Any help really appreciated!
regards
CDFS

I have the same phone from Honorbuy, I flashed twrp using the tool by Mauronofrio and from the twrp wiped all and flashed the custom rom, all went ok, no errors at all! Glad to see you have solved anyway!

Thanks for the answer... no, it's not solved for me... still a lot of bloat on the phone I can't get rid of. Do you have a link for the tool you mentioned? Could be worth a try...

Hi! I've used this tool installing it on a Windows 7 64 system:
https://forum.xda-developers.com/le-pro3/development/tool-tool-one-mauronofrio-t3580611
Then turned ON the (original LeEco stock rom) usb debug option by the rom's developer options, then downloaded the LineageOS 14.1 by Team Superluminal in the phone's internal SD (the only SD it have!) + Arm64 nano Gapps, then with the tool gave a reboot in sideload mode. Then flashed the twrp recovery by the tool, restarted in recovery mode then executed a backup of ALL the "backupable" stuff (all the original rom and data and efs), then in wipe/advanced options I wiped dalvik, system, cache, data. Then in Advanced/file manager I wiped all the SD files with a dot ( . ) at the beginning of their names, then flashed the custom rom + gapps, reboot system, wait some minutes, done!

No luck with this tool, it doesn't even find my device. Any other ideas? I've read something for the x727, where they had to flash a 19s bootloader first, but I don't want to fiddle with flashing files that are not 100% meant for the x720...
CDFS

Solved! As I could install TWRP I just went the next step and installed SuperSU (rooted the phone) in order to at least debloat stock rom. During the installation of SuperSU I saw, that SuperSU obviously patches somehow the bootloader. After checking that SuperSU worked in the ROM, I was curious if this could be the missing part I was searching for. I tried to install a LineageOS-based ROM and BINGO! it just went straight through! From my previous phones I was used to just install TWRP, wipe anything and flash desired ROM. This seems to be different on this device... so the proper procedure to be able to flash any ROMs is: Install TWRP, root stock ROM, reboot so SuperSU is fully functional, then go back into TWRP, wipe, flash what you want.
CDFS

I hate to say it, but it's still not solved. After testing Resurrection Remix, I wanted to test turbos ROMs, so went to TWRP, wiped and flashed... and got the same behaviour as before, ROM not booting. Also installing SuperSU via TWRP again didn't help, so brought back the phone to stock 023S manualy with the guide by Presterin, installed TWRP again and also SuperSU. No Errors, but flashing a different ROM didn't worked. So for now I'm back to stock, rooted it and tried to debloat it by myself. The only difference between the successful flashing and the failed was the stock version: I had the 026S-update when I rooted the phone and successfuly could flash another ROM. My guess would be that LeEco changed something in the bootloader, but I have no chance to verify this. Anyone from the devs maybe who could look into this? If you need dumos, logs or anything like that, I would be happy to help.
CDFS

This seems unrelated to bootloader.
Anyway:
1. Make sure you got the latest firmware, if not sure:
1.1. Download latest OFFICIAL ROM
1.2. Rename the rom to a 'update.zip' and place it on phone's root directory.
1.3. Reboot to fastboot and flash STOCK RECOVERY
1.4. Reboot to recovery and flash, also check wipe data.
DO NOT FLASH STOCK ROM WITH TWRP! THIS WILL NOT WORK!
That's it, you should have the latest firmware now.
After booting to stock rom, reboot a few times is recommended.
2. Download latest OFFICIAL TWRP
2.1. Flash TWRP with fastboot.
2.2. Reboot to TWRP.
2.3. Download any custom rom of your choice.
2.4. Wipe.
2.5 Flash.
Done.

You can try to flash a stock, old rom using the "Qfil/FlashOne" way as suggested by Tryzex (read his thread and other related threads), then once you have got a stable, full working phone, you can (hopefully!) wait for a LeEco OTA automatic update that can "repair" the file system/partition structure (also bootloader I hope!).
Btw, to debloat it isn't necessary to root the phone, you can keep the phone unrooted & debloated using the file manager embedded in twrp recovery to delete/replace any file/app you want. I'm sorry I can't help you better, cheers and... good luck!
PS
I see now the post from Voron00, it's a good hint!

@voron00 thx for the steps described. I'm using the most recent, official TWRP (3.1.1). Latest Official Stock seems to be 023S on their site, even though there is a 026S update. However, I did this 026S-update and rooted again, but was to cusious if flashing would work now... so I tried flashing turbos MIUI... guess what? It worked. So for whatever reason I seem to have trouble when flashing from a 023S, but no problems when flashing from 026S. I don't quite understand why you think that my problem is not related to the bootloader? As mentioned in the OP, I could see in the logs that while flashing, some roms had thrown errors regarding writing the bootpartition.
CDFS

Seems as I found the culprit, somehow. At least I could flash two other ROMs without any problems. Obviously I mixed and partly missinterpreted some steps found in different threads and howtos. I had "rm -rf for formating" ticked all the time in TWRP. My flashing procedure is now as follows:
1. in TWRP settings check that "rm -rf instead of format" is NOT ticked
2. wipe Cache, System and Data
3. repair filesystem for Cache, System and Data and check that no errors occur
4. in TWRP settings tick "rm -rf instead of format"
5. flash ROM
6. wipe Dalvik
CDFS

"rm -rf" clears all the files and directories without formatting the partition. If your partition is damaged you need a real format to obtain a reliable partition (if the "disk" isn't faulty). Perhaps in your case a real format was required to solve the problem! I always used the real format and assumed other users even so. I see you finally solved the problem!

OP5 Doesnt boot after TWRP, no_verity_op5.zip, Magisk

First of all, all my Data is backed on my Harddrive, so we dont need to take care of them.
I followed the Guide on One Plus Forum on how to unlock the Bootloader and Flash TWRP and root.
I wanted to use Magisk for root.
I followed the guide until the step with the decrypted filesystem. I installed the "no_verity_op5.zip" and magisk as statet in the guide and now my phone starts with the "g.com/abh" message and goes directly to TWRP.
When i start fastboot, bootloader and baseband is blank.
Any idea how to fix my phone?

G-Evil said:
First of all, all my Data is backed on my Harddrive, so we dont need to take care of them.
I followed the Guide on One Plus Forum on how to unlock the Bootloader and Flash TWRP and root.
I wanted to use Magisk for root.
I followed the guide until the step with the decrypted filesystem. I installed the "no_verity_op5.zip" and magisk as statet in the guide and now my phone starts with the "g.com/abh" message and goes directly to TWRP.
When i start fastboot, bootloader and baseband is blank.
Any idea how to fix my phone?
Click to expand...
Click to collapse
maybe u can try to ignore the blank screen on the fastboot and fash TWRP, if it's showing success on the cmd/powershell, then try to boot into recovery via command on the cmd/powershell. or maybe u can relock ur bootloader.
also in my experience i didn't install the "no_verity_op5.zip", i just did the unlock comand and select unlock bootloader and it's done

Sorry for the late reply, i needed a sleep.
I flashed TWRP a few times without succes, also flashing no_verity_op5.zip didnt help.
My previous idea was to use Resurrection Remix from XDA, so i flashed it and the Phone started again.
But it didnt connect to my Wifi, several restarts of the phone and of my router later i flashed OOS Again.
Maybe ill try to root it again. If it fails, ill be here again.

/data needs to be completely formatted after flashing the no_verity zip, there's no other way to remove the encryption.

The reason that's relevant is you'll get what your experiencing of you don't format /data, as it's trying to access the encrypted data that the fstab says isn't encrypted at this point and can't get further than that

1/ Backup your files on your computer
2/ Format your Data partion (format.. it's not a wipe!) you will erase all your data/internal
3/ Wipe all your others partitions (Dalvik/Cache + Cache + System)
4/ Install your rom
5/ Install no-verity zip oreo if you want have a decrypted device or flash nothing if you want have a encrypted device (more safe)
6/ Install Magisk... a 14.x Magisk version instead of a 15.x, 15x might cause bootloop after a clean flash. You can update your Magisk after the first boot

are you on 5.0.1? dirty reflashing the rom worked for me

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.

Need some help - Strange OP6T storage issues after flash

Hello, I have a T-Mobile 6T which thanks to the XDA thread about bypassing T-mobile, is running the international firmware so I didn't have to kiss their butt trying to unlock the bootloader. Yesterday I decided to try the Resurrection Remix rom since it is unclear whether the Lineage 16 rom supports the in-display fingerprint reader, and I am too busy at work and too lazy to read the entire thread to see if it does.
I followed the instructions and updated my OxyOS to the latest .15 release via TWRP which I also updated to the latest version via OTG using a USB drive because I was unable to unencrypt using the older Blu-Spark TWRP version I had installed. After the OxyOS update (on both partitions) I flashed TWRP again, rebooted to recovery and installed Pico Gapps.
I found the Resurrection Remix rom to be very buggy and I hate the way the in-display biometric works (very slow and I don't like the paw print used as fingerprint placement). Anyway I started installing apps and after 4 apps installed, it says there is no space left in storage.
Nothing will update, and when I try to check storage with any file explorer it says "access denied" or just won't load. I've tried everything. Wiped the data and did factory reset, then flashed stock rom again and same issue. What am I doing wrong?

That looks like a messed up flash. And is pretty common. Considering that A/B is still new and everyone has his own method of flashing. So assuming you can make it back to latest Stock OOS (9.0.15 right now). If you dunno how to then simple reboot to recovery, flash OOS ZIP and then TWRP. Again Reboot to Recovery from within TWRP (Reboot -> Recovery) and again flash OOS ZIP and TWRP Installer. For TWRP I recommend you to grab the latest one (3.3.1-6 as of now). Once flashed, Format Data (Wipe -> Format Data -> YES) and Reboot. Wait for it to boot up. Now you should be on Stable Stock OOS with TWRP Installed.
Now Download ROM of your Choice (RR, LOS, Bootleggers, whatever). You will also need the latest TWRP Installer (same as above) and Gapps (Nano/ Stock Recommended) and Magisk if you want to Root. Reboot to Recovery, flash ROM ZIP and TWRP Installer ZIP. Wait for it to Finish. Reboot to Recovery. Once in TWRP, again flash ROM and TWRP Installer. Once done, again. Reboot to Recovery from Within TWRP. (Read above on how to). Now, flash Gapps. Magisk if you want to Root. Once done, again do a Format Data. Reboot and be patient for ROM to boot. And then tell me wether this works or Not. Good Luck.

TWRP install impossible, phone doesn't make it past fastboot splash screen

Hey guys,
I just oem unlocked my new 6T and have access to the bootloader. As I try to install TWRP with
HTML:
fastboot boot imagename.img
my computer says that it pushes the image just fine, but my phone restarts and then never makes it past the fastboot splash screen instead of loading up TWRP.
I was following the fajita (6T) instructions from the lineage OS website.
The first time I did it it worked, but following the instructions on installing lineage and telling me to wipe and format data, both the recovery seems to be gone and i cannot fastboot boot into TWRP.
Can you help?

Seems the same with what i experienced. Have you tried installing a fastboot rom? I had my oneplus 6t bootlooped into fastboot mode even if i try to turn it off, it just boots back automatically to fastboot mode. Last resort was to flash a fastboot rom. That worked for me.

thalesian2020 said:
Hey guys,
I just oem unlocked my new 6T and have access to the bootloader. As I try to install TWRP with
HTML:
fastboot boot imagename.img
my computer says that it pushes the image just fine, but my phone restarts and then never makes it past the fastboot splash screen instead of loading up TWRP.
I was following the fajita (6T) instructions from the lineage OS website.
The first time I did it it worked, but following the instructions on installing lineage and telling me to wipe and format data, both the recovery seems to be gone and i cannot fastboot boot into TWRP.
Can you help?
Click to expand...
Click to collapse
What TWRP version are you trying to install?

jp0469 said:
What TWRP version are you trying to install?
Click to expand...
Click to collapse
I tried 3.3.1.1. and 3.2.3.0.

What you are describing, I'm going to assume you are trying to install Lineage 17. You can't install TWRP if you are going Android 10, at least that's the conclusion I've come to at this point in time. It will fail to boot or end up in crash dump mode every time you try and enter recovery if you are on a custom ROM. If you are on Android 9, it's not an issue. I believe it's OK stock as well, but I don't know haven't tried, haven't been stock in a long time.
For LOS 17, only boot the TWRP image, never boot to recovery, never run the TWRP installer. You will likely still have to format data.
I have a post here, from when I had a similar issue. (instructions)
You'll notice the OmniRom instructions don't mention installing TWRP, only booting it.
Once I was in your spot, I always went back to stock using the fastboot ROM, installed TWRP, updated (still using TWRP), then started over with my install.

Well no, i was actually trying to install Lineage 16, which is Android 9 I believe.
The problem for me is that I do not get to the point where TWRP opens after "fastboot boot"ing it. So I understand, I should use a fastboot stock ROM? Is there such a thing? Where would I find it? Or would it be an OnePlus Oxygen ROM that I can fastboot?

Quickest way to start over:
To get back straight your gonna need to access a Windows PC, and run the MSM tool. Make sure you install both OnePlus and Qualcomm drivers. ( Don't wait for Windows, just pre install the drivers) here are some links. Not my work. Please be sure to thank the developers for creating and hosting these tools ?
MSM Tool:
https://forum.xda-developers.com/oneplus-6t/how-to/tool-6t-msmdownloadtool-v4-0-oos-9-0-5-t3867448
OnePlus Drivers:
https://androidfilehost.com/?fid=11410963190603879743
Qualcomm drivers:
https://androidfilehost.com/?fid=11410963190603879743

thalesian2020 said:
Well no, i was actually trying to install Lineage 16, which is Android 9 I believe.
The problem for me is that I do not get to the point where TWRP opens after "fastboot boot"ing it. So I understand, I should use a fastboot stock ROM? Is there such a thing? Where would I find it? Or would it be an OnePlus Oxygen ROM that I can fastboot?
Click to expand...
Click to collapse
Were you on Android 10 before (OOS)? That will do that. LOS 16 is Android 9 and should have no problems installing TWRP or booting to it.. For LOS 16 I'd go back to 9.0.17, then install LOS 6T.
I posted these LOS install instructions a long time ago for another user.
Remember the MSM Tool will relock your bootloader so if something goes wrong the MSM Tool is your only choice. That is why it is always the last thing I resort to.
Thread to get Fastboot stock Roms if you want to try that route first.

Hey guys,
thank you so much for all your help. I've managed to use mauronofrios workaround here on xda to put my phone in a 9.0.17 state again (no idea what i had originally), and this way i could fastboot the twrp image again. so that worked fine, but so far flashing lineage hasnt worked, for whatever reason it seems to boot into a lineageos kind of recovery only (which i didnt even know existed).
So i guess in terms of this thread the problem is solved. Thank you again!

thalesian2020 said:
Hey guys,
thank you so much for all your help. I've managed to use mauronofrios workaround here on xda to put my phone in a 9.0.17 state again (no idea what i had originally), and this way i could fastboot the twrp image again. so that worked fine, but so far flashing lineage hasnt worked, for whatever reason it seems to boot into a lineageos kind of recovery only (which i didnt even know existed).
So i guess in terms of this thread the problem is solved. Thank you again!
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Did you see my Lineage install instructions above? LOS installs its on Recovery when you flash the ROM. When om Android 9, boot TWRP, flash the TWRP installer, reboot to Recovery, install LOS 16, flash the TWRP installer again (replaces the LOS recovery that was installed), reboot to Recovery, install gapps / magisk if desired, reboot.
Read my instructions post though, the first time install is different, as you need LOS on both slots. Updating is different as well, its much easier.
It should go smoothly.

OhioYJ said:
Did you see my Lineage install instructions above? LOS installs its on Recovery when you flash the ROM. When om Android 9, boot TWRP, flash the TWRP installer, reboot to Recovery, install LOS 16, flash the TWRP installer again (replaces the LOS recovery that was installed), reboot to Recovery, install gapps / magisk if desired, reboot.
Read my instructions post though, the first time install is different, as you need LOS on both slots. Updating is different as well, its much easier.
It should go smoothly.
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Do I need to be on Android 9 Stock when I start that process? What I did was boot into TWRP, flash TWRP installer, reboot into recovery, then format and wipe ALL partitions (except USB), then reboot into recovery again and then flash LOS, flash TWRP, reboot into recovery, flash LOS, flash TWRP, reboot system. Still no luck...

thalesian2020 said:
Do I need to be on Android 9 Stock when I start that process? What I did was boot into TWRP, flash TWRP installer, reboot into recovery, then format and wipe ALL partitions (except USB), then reboot into recovery again and then flash LOS, flash TWRP, reboot into recovery, flash LOS, flash TWRP, reboot system. Still no luck...
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Wiping, Dalvik / ART, System, and Vendor is generally a bad idea. You can do them in certain situations, this isn't one of those situations you should be wiping those though. Factory reset, means the slider on the main page of the wipe screen that says swipe to factory reset, format data is the button that says format data. Don't do anything extra. If you did, yeah I would go back to 9.0.17 using the fastboot rom again, that will put everything back on both slots.

like OhioYJ stated, don't use advanced wipe. re-run the msm tool. Then follow his instuctions. You shouldn't need to preform any manual data wiping. The process of flashing will do everything required. looks like you're almost there

Thanks guys. I will try it out and let you know.
Edit: So I finally managed to properly install LOS - OhioYJ, your instructions worked! I installed 9.0.17 and went from there without wiping any additional partitions.
One questions remains: in your instructions you mention that after installing LOS once, you can update LOS as normal and you mention doing it via the recovery with flashing TWRP or GAPPS later again. Is it possible to do the update via the normal update function of LOS as well? Or will that overwrite TWRP?
You guys are awesome. Thank you so much for your help!

I seem to be stuck on the fastboot screen as well. Being on a MAC, anytime i try to do something in fastboot it goes straight back to the fastboot screen. I Thought I was on Android 10.0 trying to install recovery for that lead to bootloop of fastboot, tried using the Pie recovery and same thing. I am open to suggestions.
Thanks.

OhioYJ said:
What you are describing, I'm going to assume you are trying to install Lineage 17. You can't install TWRP if you are going Android 10, at least that's the conclusion I've come to at this point in time. It will fail to boot or end up in crash dump mode every time you try and enter recovery if you are on a custom ROM. If you are on Android 9, it's not an issue. I believe it's OK stock as well, but I don't know haven't tried, haven't been stock in a long time.
For LOS 17, only boot the TWRP image, never boot to recovery, never run the TWRP installer. You will likely still have to format data.
I have a post here, from when I had a similar issue. (instructions)
You'll notice the OmniRom instructions don't mention installing TWRP, only booting it.
Once I was in your spot, I always went back to stock using the fastboot ROM, installed TWRP, updated (still using TWRP), then started over with my install.
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Twrp is working fine with Android 10, using mauronofrio version and magisk 20.2

callumbr1 said:
Twrp is working fine with Android 10, using mauronofrio version and magisk 20.2
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Yeah it starting to seem like it maybe isolated to Lineage. You cant install TWRP with LOS 17. Someone else mentioned in the Omni thread that it worked. This thread is about Lineage, but that should be clarified, or clearer.