OnePlus 8T (TMO) KB2007 bricked after LineageOS flash?

[FreeDee]

Hi, I did something stupid and need some help please.

I got the bootloader unlock code for my KB2007 - Unlock went well, no issues.
Then I proceeded to download and install the latest official TWRP - Also no issues, I was in the custom recovery, created some backups etc.
After that, I followed the instructions to install Lineage OS as posted here:

Install LineageOS on kebab | LineageOS Wiki

wiki.lineageos.org

I flashed the dtbo and vbmeta partitions as instructed and proceeded with adb sideloading the copy-partitions-20220613-signed.zip file - Somewhere around here is where things went south.
I was not able to access/read my data partition anymore, and attempted to flash the lineage-recovery. After a reboot, I'm now stuck in the bootloader (fastboot). When I select Recovery mode, the phone just goes black. I also can no longer "fastboot boot twrp.img" - Error: "Failed to load/authenticate boot image: Load Error".
After checking the guide one more time I noticed it says the device has to be on Android 12, which mine was not (it was still in factory condition - Android 11). So that was likely the problem.

So now the big question is can I recover from this state? If yes, what's the best way to do so?

Thanks so much!

 

[Rootk1t]

Hi, I did something stupid and need some help please.

I got the bootloader unlock code for my KB2007 - Unlock went well, no issues.
Then I proceeded to download and install the latest official TWRP - Also no issues, I was in the custom recovery, created some backups etc.
After that, I followed the instructions to install Lineage OS as posted here:

Install LineageOS on kebab | LineageOS Wiki

wiki.lineageos.org

I flashed the dtbo and vbmeta partitions as instructed and proceeded with adb sideloading the copy-partitions-20220613-signed.zip file - Somewhere around here is where things went south.
I was not able to access/read my data partition anymore, and attempted to flash the lineage-recovery. After a reboot, I'm now stuck in the bootloader (fastboot). When I select Recovery mode, the phone just goes black. I also can no longer "fastboot boot twrp.img" - Error: "Failed to load/authenticate boot image: Load Error".
After checking the guide one more time I noticed it says the device has to be on Android 12, which mine was not (it was still in factory condition - Android 11). So that was likely the problem.

So now the big question is can I recover from this state? If yes, what's the best way to do so?

Thanks so much!

Restore to stock via MSM.

 

[IAAxl]

You must update to OxygenOS 12 before installing lineageos 19.1 or you will brick.

The lineagsos guide is wrong and I bricked my device by following it too.

For now, you can only unbrick it with msmtool.

[OP8T][OOS TMO KB09CB] Unbrick tool to restore your device to OxygenOS

Disclaimer: By attempting any of the processes listed in this thread you accept full responsibility for your actions. I will not be held responsible if your device stops working, catches fire, or turns into a hipster and claims to have been...

forum.xda-developers.com

Then OTA to OOS 12, then install LOS19.1.

 

[FreeDee]

Thanks guys! I was able to restore the device using the MSM tool
I intend to keep it on OOS 11 (and potentially flash LOS18.1), because KB2007 is the T-Mobile variant and based on what I read dual sim only works with OOS 11.
The problem is it is becoming increasingly difficult to find instructions (or even downloads) for anything but the very latest versions :/

 

[Rootk1t]

Thanks guys! I was able to restore the device using the MSM tool
I intend to keep it on OOS 11 (and potentially flash LOS18.1), because KB2007 is the T-Mobile variant and based on what I read dual sim only works with OOS 11.
The problem is it is becoming increasingly difficult to find instructions (or even downloads) for anything but the very latest versions :/

You can also use KB2007 OOS 13 beta 1 which works with dual sims.

 

[FreeDee]

You can also use KB2007 OOS 13 beta 1 which works with dual sims.

Thanks! Yeah, I also read about that, and it does indeed sound like a potential way to go.
Do you know if anyone has figured out yet what makes this "beta 1" special in that it allows dual sims? I think I also read it's no longer possible with beta 2.

 

[Rootk1t]

Do you know if anyone has figured out yet what makes this "beta 1" special in that it allows dual sims? I think I also read it's no longer possible with beta 2.

As far as i know, it's still unknown what makes beta 1 work in dual-sim mode.