[Android General] pndwal:
Not off topic at all in this thread. :)

I don't know much about Kingroot except I'd avoid using it at all costs :) . [It has been confirmed KR sends your data to their servers incl. IMEI numbers, etc. While KR states here on XDA they don't save or misuse this data, this alone is enough to put me off. Call me paranoid, but there is a lot riding their word. Also, KR has fairly limited superuser functionality compared to SuperSU and Magisk]

Partly due to this, I'd back up everything and start fresh.

Also, most modders avoid rooting any device without installing custom recovery first. As you learned, if something goes wrong you need a 'Recovery'.

OP here is gone (see post #339) and all his file links are broken.

This thread will continue to be a valuable resource regarding past progress with TB3-850F, and despite threads title, a general discussion on TB3-850F continues here for now. It lately relates largely to new LOS14.1.

Modders seldom use stock recovery interface, especially when TWRP is available, so I'm pretty sure no one has added English.

And yes, I'd backup, reset and start fresh as mentioned. The following info should help:

For my re-posted Useful Stuff (Including UNLOCKING / ROOTING Instructions, latest stock ROM, TWRP recovery incl. How to Enter TWRP, etc, see post #404, page 41 this thread. (Can use Magisk instead of SuperSU these days.)

Nb. This contains convoluted steps to make TWRP stick. These should only be necessary if using stock ROM with root and TWRP as stock ROM replaces TWRP with that Chinese stock recovery by default (wiping TWRP) on bootup if it detects a modified recovery. If moving to LOS14.1, ignore steps related obtaining root, avoid booting stock ROM, install TWRP, and then LOS, and then root (by flashing Magisk or SuperSU) should just stick.

Post re importance of nandroid backup as soon you have TWRP: Post #252, page 26 this thread.

Thread by [MENTION=8243079]r&xp[/MENTION] for unbricking, especially if you can't get SPFT to connect to reinstall stock, here:

https://xdaforums.com/android/help/lenovo-tab-3-8-tb3-850f-unbrick-root-t3598727

Nb. This contains fairly old ROM (s100023), so probably best to read his steps here, but use latest full ROM in my 'Useful Stuff' post above (lenovo-tab3-a8-tb3-850f_s100030_161209_row. Will update to s100031 via OTA later). This contains all needed windows drivers and files too (vcom driver, SPFT etc), and I'd use this included SPFT even if you have a later version as some have had unexpected problems with later versions. Entering TWRP with button combo is not as difficult as he thinks either (- see my Useful Stuff post). The volume down trick mentioned is however key to a successful USB connection.

I'd wipe everything ROM related (- data, cache, system, dalvik) in TWRP for a clean ROM flash (- this should also remove all traces of kingroot), and then give our new LOS14.1 a go.

NEW THREAD For Stable & Near Bug Free TB3-850F LOS ROM, here:

https://xdaforums.com/android/general/rom-lineageos-14-1-lenovo-tab-3-8-tb3-t3900320

Already very stable, and a further update comprising small tweaks and improvements by [MENTION=9720847]AeonFlux1603[/MENTION] & [MENTION=8548258]wezroot2k[/MENTION] is imminent.

Glad you've got more than one - your wife may need one as a distraction while you fix TB3-850F.

Nb. Just reading is much better for ones nerves - modding and recovery are often the cause of temporary insanity. (Sorry this warning is a bit late for you ;) .)

Hope this helps, you get back to your reading soon, and all the best re your wife's health too. PW.