[Lenovo Legion Y700] Joncka:
Windows guide, might work for other aswell.

I finally solved my problem with my Lenovo Y700 tablet being stuck in bootloop mode due to trying to flash Magisk boot with a mismatched firmware version. This resulted in the UI constantly crashing, and I could not connect to Wi-Fi, and other problems...

I tried flashing back to stock with QFIL, which put the device in a bootloop. I will explain why later on.

I also lost recovery mode due to trying to solve the problem, and now I was stuck with either showing the bootloader screen, or restarting the tablet, which brought me back to the bootloader.

So the tablet was now genuinely useless. This is what I did to bring back the stock ROM and later flash to crDroid 8.10.

Flashing boot.img, system.img or recovery.img was no luck.

First off, there is no need to have unlocked "USB debugging" before your tablet bricked.

Second, you don't need to have your "sn.img" file from Lenovo, you can unlock the bootloader using fastboot commands.

Fastboot commands works on the bootloader screen, without having ADB connection.

Start by downloading these four files:

Platform tools r33.0.2

QPST_2.7.496

Qualcomm_USB_Driver_v1.0

Lenovo Y700 tablet stock ROM

We'll start by unlocking your bootloader. You can do this from the bootloader screen. If you for some reason can enter recovery mode, enter fastboot.

1. Connect your tablet to your PC.

2. Open a terminal windows in the ADB folder. On Windows 11 this can be done by right-clicking inside the ADB folder and select "Open in terminal". If you don't have that option, try Shift + Right-click. If that doesn't work, you can always start the terminal by pressing Win + R, and type in "cmd" without citations. Now you have to navigate to your ADB folder by typing

cd (here you'll type in the location of your ADB folder)

Without the brackets.

3. When located, type in

fastboot devices

You should see your tablet in the list.

If not, try using another cable or USB port on your PC.

4. Now type in

fastboot oem unlock-go

Restart your tablet, and it should now say "unlocked" under "DEVICE STATE" in the bootloader.

5. Now you can start by installing the programs on your PC, QTPS, Qualcomm driver and platform tools.

6. Extract ALL files from your stock ROM to the "bin" folder in QTPS location (usually C:\Program Files (x86)\Qualcomm\QPST).

This will help with Sahara errors in QFIL.

7. Open QFIL from your QTPS bin folder, it installs with QTPS. Don't worry if it shows "No Port Available", we'll get to that. Your configuration should look like this:

View attachment 5741653

Your main window should look like this:

View attachment 5741651

Don't worry about the "status" window.

Hit "browse" in the "Programmer Path" window, and navigate to your QTPS bin folder. Select "prog_firehose_ddr.elf"

Hit "Load XML", and navigate to your QTPS bin folder. Now, select ALL of the "rawprogram" files (my first mistake, I only selected the "rawprogram_unsparse0.xml" file on first flash)

In the next window, select ALL of the "patch" files (my second mistake, I only selected the "patch0.xml file" on first flash).

Without doing this, you will only flash a portion of the ROM, and not all of the partitions needed.

8. Now it's time to reboot you tablet into EDL mode to be able to flash. Start your tablet by pressing VolUp + Power button.

If you can't turn off your tablet when connected to PC, just select "Power off", and just hold the VolUp button as soon as the device vibrates and reboots, keep holding until the screen flickers and turns off.

9. Now QFIL should detect the Qualcomm 9008 port. If not, hit "Select Port" and select the Qualcomm 9008 port.

10. Hit the now available "Download" button, and the flashing should begin. Allow it to run its course, and it should reboot the tablet when done. Might take a while.

If flashing won't start properly, you might have waited too long between entering EDL mode and hitting the "Download" button.

If so, disconnect your device, which might now be "dead".

Don't worry, you can fix this be holding VolUp + VolDown + Power button for a long time, say about a minute to be sure. Release the Volume keys some second before releasing the Power button.

Hit the power button again, and the tablet should boot to bootloader screen again.

Repeat the steps to enter EDL mode, and now hit the "Download" button in QFIL when it becomes available, don't wait too long.

You're done! ​

I recommend opening "Settings", enable "Developer" option, by pressing the "Build number" on the "About tablet" screen repeatedly until a pop-up appears saying "You are now a developer".

Open "Developer options" and hit "Enable USB debugging", it will allow you to run ADB commands from your platform tools folder.

If you want, you can again open the terminal in the platform tools folder and type

adb devices

It should now show your device in the list.

Now you can uncheck the "OEM unlocking" in the "Developer options" which should let you get OTA updates when available.

There are plenty of guides on how to flash different GSI's like crDroid, so I won't cover that here.

Enjoy your tablet!