Database Users

Easiest Method To Install Any Custom Rom - Universal 7.XX/8.XX

Hey guys,
So recently I tried a few custom roms and noticed that the steps for all roms are slightly diffferent and that confused. Hence decided to try everything available and come to a easiest step by step conclusion:
Steps :
At the time of writing this guide I was on codeworkx universal TWRP running stock OOS 4.7.6 with Magisk 15.2. But the steps would work from any rom to any rom.
1) Flash codeworx universal TWRp from here : https://goo.gl/yXx2sK
2) Boot into twrp and using your pattern/pin decrypt data, yes thats the good part no matter if you are on stable or custom be it android 7.1.1/8.0/8.1 this recovery is able to decrypt all roms.
3) Make a nandroid backup and copy all contents of your internal storage to a pc/ choose the backup method of your choice.
4) Make sure you have at least 50% battery charged.
5) In twrp go to wipe . format data type yes and tick
6) Reboot to recovery
7) Perform a factory reset also wipe internal storage.
8) While in twrp copy the rom and firmware and gapps to your phone
9) Flash first the firmware if needed by the rom, then flash the rom and then gapps and then dm verity zip if needed by the rom. Wipe cache and dalvik. (note if you are flashing a stock rom please flash magisk and then make the first boot otherwise TWRP will be erased)
10) Boot into rom and set it up
11) Flash magisk or supersu if needed.
Heres a step by step video :
Credits :
@Funk Wizard
 @codeworkx
xda developers
lineage os
team twrp
oneplus
Please note : Do this at your own risk. I would not be responsible for any damage.
If I have missed any names please PM me I will ensure i add it.​

Why all this codeworx TWRP hype all of the sudden? Bluspark has never let me down yet. What is the difference between the two?

It's good if you add DM verity to the list as "if needed" because certain custom ROMs require it.

I'll be looking at this thread at some point in the future. Thanks.

Anyone followed the above and have comments to make ?

after flash any rom black screen and blue LED
any help

Always boot in recovery mode after an update

Hi,
I was updating my OP6T to the new version (Magisk + Xxx NoLimits), but after the reboot post-update the device started to reboot to recovery after it booted. So I've tried to delete Magisk but the problem was still present, so I've decided to download the latest Oxygen ROM from the OnePlus and flash it from TWRP, but after flashing, the device started to always boot to recovery (before the OnePlus boot animation).
At least i tried to restore a nandroid backup of 1 month ago (System, Boot and Data), but still the device after the restore still boot to recovery before the boot animation.
I've only tried the system reboot (I've not tried to force boot another slot).
Do you have a solution to try before formatting the internal storage?
Thanks
Edit: After unistalling magisk and reflashing it again, now the device boots again, but immediately after (when the lock screen appear) the device reboot automatically to recovery again

Try this:
- in twrp , dirty flash the rom you are using (Oxygen os)
- factory reset
- flash twrp (the latest the better)
- flash Magisk 19.1
Reboot to system.
If this not working, Format data will work.

null0seven said:
Try this:
- in twrp , dirty flash the rom you are using (Oxygen os)
- factory reset
- flash twrp (the latest the better)
- flash Magisk 19.1
Reboot to system.
If this not working, Format data will work.
Click to expand...
Click to collapse
Factory reset from TWRP?

yes

null0seven said:
yes
Click to expand...
Click to collapse
So, do you mean the classic Wipe data, cache and dalvik?

https://forum.xda-developers.com/oneplus-6t/how-to/official-oxygenos-9-0-4-ota-oneplus-6t-t3860953
TWRP Users
1. Boot into TWRP and Flash the Latest Magisk Uninstaller
2. Flash the latest Full Oxygen OS Zip
3. Flash the TWRP installer Zip
4. Reboot to RECOVERY to make sure TWRP stays and continue to root.
5. Flash the Latest Magisk to maintain root
6. Reboot System and Enjoy the latest firmware without any data loss
Click to expand...
Click to collapse
I am guessing you skipped the first step...
Try this:
Flash the OTA zip
Reboot (you will be unrooted and with stock recovery)
Boot to TWRP through ADB
Flash magisk unistaller
Reboot
Boot to TWRP through ADB
Flash OTA zip
Flash TWRP
Reboot to TWRP
Flash magisk

Galeanatur said:
https://forum.xda-developers.com/oneplus-6t/how-to/official-oxygenos-9-0-4-ota-oneplus-6t-t3860953
I am guessing you skipped the first step...
Try this:
Flash the OTA zip
Reboot (you will be unrooted and with stock recovery)
Boot to TWRP through ADB
Flash magisk unistaller
Reboot
Boot to TWRP through ADB
Flash OTA zip
Flash TWRP
Reboot to TWRP
Flash magisk
Click to expand...
Click to collapse
I don't have the OTA but the full rom, isn't simplier to update with the full ROM?
I think I'm going to try the null0seven's solution

null0seven said:
Try this:
- in twrp , dirty flash the rom you are using (Oxygen os)
- factory reset
- flash twrp (the latest the better)
- flash Magisk 19.1
Reboot to system.
If this not working, Format data will work.
Click to expand...
Click to collapse
Ok, I've done this and actually is even worse, the device started to boot in recovery again and TWRP doesn't recognize that the internal storage is crypted, so i can't even access the internal storage (it shows only strange folders), so, now I can't flash the nandroid backup anymore.

I also mean FULL rom .zip.
Format data in twrp or in Fastboot. Or use MSM tool .
https://forum.xda-developers.com/oneplus-6t/how-to/tool-6t-msmdownloadtool-v4-0-oos-9-0-5-t3867448
all of them will wipe ALL in youre phone, but it will work.

null0seven said:
I also mean FULL rom .zip.
Format data in twrp or in Fastboot. Or use MSM tool .
https://forum.xda-developers.com/oneplus-6t/how-to/tool-6t-msmdownloadtool-v4-0-oos-9-0-5-t3867448
all of them will wipe ALL in youre phone, but it will work.
Click to expand...
Click to collapse
So I've to Full wipe and then adb sideload the ROM? Because at the current state I can't even boot the device, it always starts in TWRP
Edit: I've also tried the blue_spark's version but nothing changed, TWRP can't recognize the encrypted storage

you can try this first.
https://forum.xda-developers.com/oneplus-6t/how-to/rom-stock-fastboot-roms-oneplus-6t-t3862516

fuji97 said:
Hi,
I was updating my OP6T to the new version (Magisk + Xxx NoLimits), but after the reboot post-update the device started to reboot to recovery after it booted. So I've tried to delete Magisk but the problem was still present, so I've decided to download the latest Oxygen ROM from the OnePlus and flash it from TWRP, but after flashing, the device started to always boot to recovery (before the OnePlus boot animation).
At least i tried to restore a nandroid backup of 1 month ago (System, Boot and Data), but still the device after the restore still boot to recovery before the boot animation.
I've only tried the system reboot (I've not tried to force boot another slot).
Do you have a solution to try before formatting the internal storage?
Thanks
Edit: After unistalling magisk and reflashing it again, now the device boots again, but immediately after (when the lock screen appear) the device reboot automatically to recovery again
Click to expand...
Click to collapse
When you're saying you're flashing the full ROM after wiping, are you meaning the xxx no limit? If so this isn't an os rom it's just a magisk module rom that's an add on to oxygen os. You need to wipe and flash the latest oxygen os rom, stable or beta which ever you're using, then flash TWRP, flash your os again on the other slot, flash TWRP, flash magisk, if your system boots fine then flash the xxx no limits rom in twrp.

ebproject said:
When you're saying you're flashing the full ROM after wiping, are you meaning the xxx no limit? If so this isn't an os rom it's just a magisk module rom that's an add on to oxygen os. You need to wipe and flash the latest oxygen os rom, stable or beta which ever you're using, then flash TWRP, flash your os again on the other slot, flash TWRP, flash magisk, if your system boots fine then flash the xxx no limits rom in twrp.
Click to expand...
Click to collapse
No, I flashed the full ROM downloaded from the OnePlus server

Have you tried formatting data?

Cablespider said:
Format data.
Click to expand...
Click to collapse
So, full format data and flash rom + TWRP + Magisk?

fuji97 said:
No, I flashed the full ROM downloaded from the OnePlus server
Click to expand...
Click to collapse
You're best bet is to use the MSM tool
https://forum.xda-developers.com/oneplus-6t/how-to/tool-6t-msmdownloadtool-v4-0-oos-9-0-5-t3867448

Ok, I've decided to use MSM to recover the device, I've lost the internal storage, but at least the device is working again.
Thank you to everyone who helped me in this thread

fuji97 said:
Ok, I've decided to use MSM to recover the device, I've lost the internal storage, but at least the device is working again.
Thank you to everyone who helped me in this thread
Click to expand...
Click to collapse
Maybe it was a Magisk module that caused it. I removed pixel module from Magisk and it done the same to me.

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.

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.
Click to expand...
Click to collapse
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?

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