[Android General] john3voltas:
[MENTION=7383447]MotoJunkie01[/MENTION]

I can't possibly thank you enough for your work here, at least on the Lenovo TB3-850F topics.

Having said that, I must also point out that this topic has a couple of rough edges that could be ironed out.

First, as [MENTION=5950506]stephenwhite[/MENTION] has pointed out, since the text is not clear enough, some of us are not rebooting after fastboot oem unlock and that is putting us on endless bootloops that fortunately can be beaten using SP Flash Tool.

Second, by not putting it clear enough in the text prior to the command, a fastboot oem unlock forces the tablet into a full factory reset and loosing ALL photos, videos and documents on the tablet. When I read your following sentence I was petrified but unfortunately there was nothing else I could do at that point because the tablet had already gone into a bootloop.

Third, I think we could benefit a lot if the text was put in simpler sentences and/or commands instead of full paragraphs.

Later today I'll try to find time to publish a revised version of your first post that newcomers such as myself would most certainly benefit a lot in the coming future. Yet, first I have to find my way of installing your stock rom without bootloops.

But all in all, thanks a bunch for your hard work.

Cheers

PS:

Okay, I've tried your 1st post instructions once again. Gone a little better but still not there yet.

If I would re-write your instructions, this is how it would look like:

INSTRUCTIONS:

1. First and foremost, unlocking the bootloader is necessary. Also, this step is a good place to make some requisite preparations.
1.1 Power on your Tab 3 and select SETTINGS once booted up.
1.2 Go to ABOUT DEVICE, find BUILD NUMBER, and tap it 7 or 8 times until DEVELOPER OPTIONS is enabled.
1.3 Leave the ABOUT DEVICE submenu and open the In DEVELOPER OPTIONS.
1.4 tick to enabled both OEM UNLOCKING and USB DEBUGGING option.
1.5 On your PC, install the Minimal ADB & Fastboot utilities, the ADB Driver Installer, and the Lenovo USB Driver Installer.
1.6 Connect your Tab 3 to your PC with the supplied (or quality equivalent) OEM charging/syncing cable.
1.7 Open a command window in your ADB/Fastboot directory, by holding SHIFT and right clicking in the desired path.
1.7.1 In the command window, type:
1.7.2 adb devices & press RETURN.
If your device is connected properly, the command window will display a string of numbers/letters, which represent your device's serial number. If your serial number does not appear in the window, try changing USB ports, change syncing cables, or try reinstalling the ADB Drivers.
Once properly connected, type:
1.7.3 adb reboot bootloader & press RETURN.
Your tablet should boot into Fastboot Mode, which will be displayed in white bold letters on your device's display once complete.

PAY EXTRA CAREFUL ATTENTION TO THIS NEXT STEP!
After completing the next step YOU WILL LOSE ANY UNSAVED VIDEOS, MUSIC, PERSONAL FILES, ETC.
Please make sure to backup in order to complete the next step.
After issuing this next step, your device will prompt you to press Volume Up to proceed with unlocking the bootloader, or Volume Down to cancel the process.
WARNING: Choosing Yes/VOL UP will start the procedure to UNLOCKING THE BOOTLOADER and that INITIATES A FACTORY DATA RESET losing all your userdata.
1.7.4 fastboot oem unlock & press RETURN.
1.7.5 reboot ('fastboot reboot' didn't work for me. Even though it accepted the command, it stayed in fastboot mode an I had to press the power button for ~10 seconds)

2. Now that your bootloader is unlocked, you are ready to flash TWRP.
2.1 Download the twrp.img file from my link
2.2 Save twrp.img to your PC in the ADB/Fastboot path/directory.
2.2.1 Also, save a copy of the twrp.img on your device's internal storage or external micro SD card. (ie /Downloads)
Since your device underwent a factory data reset, you will again need to enable DEVELOPER OPTIONS & tick OEM UNLOCKING & USB DEBUGGING as you did in Step 1.
2.3 please repeat steps 1.2 and 1.3
2.4 Re-open a command window from your ADB folder and ensure a proper connecion and type:
2.5 adb reboot bootloader & press RETURN.
Once in Fastboot Mode, type:
2.6 fastboot boot twrp.img & RETURN.
EXTREMELY IMPORTANT NOTE: this device's boot image is secured with dm-verity.
Leave the /system partition as read-only when prompted by TWRP. Mounting /system as read/write at this point will result in a boot loop.
Flashing SuperSU, as outlined in Step 3, will patch dm-verity and fix this.
Now your tablet should have rebooted into TWRP automatically.
2.7 On TWRP's first screen hit the 'KEEP READ ONLY' button.
2.8 From the TWRP main menu
2.8.1 select INSTALL
2.8.2 select the 'Install Image' option in the bottom right of the screen
2.8.3 navigate to the location where you saved twrp.img in device storage or external storage (step 2.2)
2.8.4 select twrp.img
2.8.5 choose 'Recovery' in the Select Partition option.
2.8.6 swipe to commence the installation.
Don't press the 'REBOOT SYSTEM' button!!
2.8.7 select 'Back' button
2.8.8 select the back <| 'triangle button' on the tray bar TWICE to go back to the main menu.
2.8.9 select REBOOT
2.8.10 select RECOVERY
Your TWRP custom recovery should now be successfully installed on your device's recovery partition.
Your tablet should have rebooted and gone straight to the TWRP installed on your recovery partition.

3. Now, it is time to root this tablet.
3.1 Download & save a copy of the SuperSU v2.82-SR5 zip file to the tablet's internal or external storage.
3.2 In TWRP main menu
3.2.1 select INSTALL & navigate to the saved SuperSU zip.
3.2.2 Commence with installation.
Systemless root mode will unpack, modify, repack and flash the patched boot image.
Once done, reboot system.
Your Android OS should now have full systemless root, and the /system partition may now safely mount as read/write.