xdadev_user11 said:

Try this zip file, be sure to boot to fastbootd mode to flash the custom signed vbmeta file first and then the patched signed magisk file

Hi xdadev_user11

Great guide... Just like other members here, I was able to follow your steps to unlock the bootloader, but seem to be getting stuck in bootloops when flashing your imgs.

So far, I've managed to factory restore by getting to a Chinese-based recovery menu by long pressing Volume Up when turning it on. So I kind of reverse the bad flash this way...

Really need root on the device though because all my daughter's games are backed up from a rooted Samsung using Alpha Backup and TiTaBackup...so need to get her games' progress back from those backups.

Would you be so kind as to make me the right imgs for my config?

My details are
Teclast T40 Pro_ROW
Model: T1B1
Update version: 1.03_20220722
Screenshots attached

Not sure how to dump my current imgs..
If that would make it easier for you to patch, please let me know how to?

For that matter, I can't even access the firmware pages on the Teclast site... I'm getting a 404...

Much appreciate your assistance, in advance

thkgop001 said:

Hi xdadev_user11

Great guide... Just like other members here, I was able to follow your steps to unlock the bootloader, but seem to be getting stuck in bootloops when flashing your imgs.

So far, I've managed to factory restore by getting to a Chinese-based recovery menu by long pressing Volume Up when turning it on. So I kind of reverse the bad flash this way...

Really need root on the device though because all my daughter's games are backed up from a rooted Samsung using Alpha Backup and TiTaBackup...so need to get her games' progress back from those backups.

Would you be so kind as to make me the right imgs for my config?

My details are
Teclast T40 Pro_ROW
Model: T1B1
Update version: 1.03_20220722
Screenshots attached

Not sure how to dump my current imgs..
If that would make it easier for you to patch, please let me know how to?

For that matter, I can't even access the firmware pages on the Teclast site... I'm getting a 404...

Much appreciate your assistance, in advance

Click to expand...

Have you tried flashing these files?

Teclast T40 Plus Root

Received the tablet in the mail, and now looking to root via Magisk (and ideally a custom recovery like TWRP). I found this video describing a way to download the stock ROM from Teclast: Has anyone achieved root on this device? Can anyone...

forum.xda-developers.com

xdadev_user11 said:

Have you tried flashing these files?

Teclast T40 Plus Root

Received the tablet in the mail, and now looking to root via Magisk (and ideally a custom recovery like TWRP). I found this video describing a way to download the stock ROM from Teclast: Has anyone achieved root on this device? Can anyone...

forum.xda-developers.com

Also the firmware page is in this link

FirmwareDownload

en.teclast.com

Click to expand...

Super quick response - awesome!

Yes, just tried the imgs from that link now.

No dice - still in a boot loop:

After putting in your T1B1 imgs into the platform folder, these are my commands:

C:\Users\Administrator\Downloads\platform-tools>fastboot flash vbmeta vbmeta.img
Sending 'vbmeta_b' (1024 KB) OKAY [ 0.030s]
Writing 'vbmeta_b' OKAY [ 0.157s]
Finished. Total time: 0.193s

C:\Users\Administrator\Downloads\platform-tools>fastboot reboot
Rebooting OKAY [ 0.001s]
Finished. Total time: 0.001s

the tablet gets stuck in a boot loop on the splash screen. So I can't move on to the next step....

Onto the firmware page, guess my other device was geoblocked or something; because now I can see these options for the T1B1:

thkgop001 said:

Super quick response - awesome!

Yes, just tried the imgs from that link now.

No dice - still in a boot loop:

After putting in your T1B1 imgs into the platform folder, these are my commands:

C:\Users\Administrator\Downloads\platform-tools>fastboot flash vbmeta vbmeta.img
Sending 'vbmeta_b' (1024 KB) OKAY [ 0.030s]
Writing 'vbmeta_b' OKAY [ 0.157s]
Finished. Total time: 0.193s

C:\Users\Administrator\Downloads\platform-tools>fastboot reboot
Rebooting OKAY [ 0.001s]
Finished. Total time: 0.001s

the tablet gets stuck in a boot loop on the splash screen. So I can't move on to the next step....

Onto the firmware page, guess my other device was geoblocked or something; because now I can see these options for the T1B1:

View attachment 5691623
Which one should I choose? My tablet is the _ROW, so does that mean I should stick with middle line link and not the top link?

Also, after applying the OTA update, my current firmware version is neither one of these - it's actually 1.03_20220722.

What should I try next?

Thanks

Click to expand...

Have you tried flashing the T40 Pro(T1B1)_Android 11.0_ROW 2022-06-6 firmware and then flashing my vbmeta and magisk img files before updating to 1.03_20220722?

xdadev_user11 said:

Have you tried flashing the T40 Pro(T1B1)_Android 11.0_ROW 2022-06-6 firmware and then flashing my vbmeta and magisk img files before updating to 1.03_20220722?

Hey xdadev_user11,

Appreciate all the help - I'm definitely one step closer to the end but now I'm stuck in a (much shorter) boot loop after trying to flash the magisk-patched boot img to the boot partition.

So here are my steps as of now:

1.
Successfully flashed the firmware from T40 Pro(T1B1)_Android 11.0_ROW_V1.02_SZ (this is from middle link from my table screenshot above).
I can see that Android boots fine (like a new factory device) and is back on the 1.02_20220523.
At this point, I leave the tablet offline i.e. I do not attempt any OTA update. All I do is enable USB debugging again. No security pass-code setups or anything like that...

2.
Enter fastbootd
Flash your vbmeta using
fastboot flash vbmeta vbmeta-sign-custom.img
When rebooting, it still gets stuck in a boot loop - though the end of the loop is the Teclast splash screen with the moving circuitry
I managed to get around this boot loop by repeating Step 1 and then flashing your vbmeta using
fastboot --disable-verity --disable-verification flash vbmeta_b vbmeta-sign-custom.img
Note that I had to explicity flash to vbmeta_b and not just vb_meta
I know you said earlier that you don't need to do this, but for some reason, it works for me
At this point, I can boot into Android consistently.

3.
Enter fastbootd
Flash your boot using
fastboot flash boot magisk.img
When rebooting, it gets stuck in a boot loop - this time the boot loop is much shorter.
I see this text on the device screen - right at the top
INFO: LOCK FLAG IS : UNLOCK!!!
Then it reboots over and over.
Usually (if not stuck in a boot loop) a second line shows up
WARNING: LOCK FLAG IS UNLOCK, SKIP VERIFY!!!
and the device continues onto to booting Android

4.
To try and fix it myself, I tried this
Repeated Steps 1 and 2
Downloaded and installed the latest magisk apk onto the device: Magisk-v25.2.apk
I grabbed the stock boot.img from the firmware folder from the folder on my PC at
FirmwareFlash/Upgrade Tools/ImageFiles
Copied them onto the device
Used Magisk on the device to patch the original boot.img to magisk_patched-25200_3ZQLR.img
Moved this patched boot.img back to my PC
Tried this new file on Step 3
Same boot loop

5.
Thinking that the verity issue is causing the bootloop, I tried this command below using both your patched boot.img (from Step 3) as well as my patched boot.img (from Step 4)
fastboot --disable-verity --disable-verification flash boot magisk_patched-25200_3ZQLR.img
Same boot loop

So, at this point, I've run out of ideas...and asking for your help, yet again! I think I'm really close to finally getting root....because I'm basically boot looping at the very last step in your guide.

Here (attached) are the stock boot.img and vbmeta.img files from my stock firmware folder.

I'm guessing you need to patch my boot.img file in some special way that I'm not doing yet?

If you need any more details from me, please let me know?

Need you to do some magic....before I have no more hair left to pull out I've been at this for practically 2 days now!

Thanks in advance; much appreciated.