[Samsung Galaxy Tab S6 Guides, News, & Discussion] VeEuzUKY:
Dearest jaidev.s.. it's quite of a long story (and a surprising one at that) as I have been flashing, testing and even helping build several custom ROMs for Samsung deviced in the past 12 years without ever getting stuck in a truly unforeseen situation.

To make a very long story short, after doing all my homework through all the available threads and feedback I could find on the matter, I ventured to unlock the bootloader, install TWRP custom recovery, required custom kernel and magisc root files for my T865. And yes, I followed precisely the available guides on it from our community. Things all went pretty much as planned and I eventually booted into a successful fully rooted session on my tablet. I tested all of the tablet's native apps and functionality, installed Root Explorer and a few other apps that I had backed-up APKs for. My session was about 30 minutes long, I never connect to any data in stayed always offline, after which I decided to reboot the tablet. And then, meltdown.

The tablet immediately refused to restart again, completely bypassing the initial standard Samsung splash screen, and going directly into a warning screen that it had been locked due to the "installation of unauthorised software". From that point on any attempt to get the tablet from that state or to simply flash the stock firmware, failed completely. With the help of some other developers we all ventured together if my firmware was actually from another region, all of which I tried without any success. Eventually the tablet got stuck in a state that would not even turn off anymore even if I forced it via the volume down and power button commands. I eventually just waited out until the battery exhausted itself and then that was that.

Upon taking it to Samsung for repair where within seconds they realised that I had unlocked the bootloader and had tried to install a custom recovery, they came back about half an hour later explaining me that the hardware itself would not read or write any data any more despite their efforts, for which they would have to replace the mainboard.

I am yet to try and understand how the the tablet stopped functioning upon a reboot when up to that point everything had been flashed correctly and I had managed to do a session with everything properly configured. This said, I'm facing a $550 repair to what was an $800 tablet purchased just 10 days ago. I will obviously now not venture to try to install custom recovery again. I believe my tablet might have been a one-off with some sort of a preexisting hardware glitch that got ignited by the custom flashing that I did.. I really don't know and it really doesn't matter. At this point as I am about to collect the repaired tablet in a couple of days, the only thing I am interested in doing (a must for me on any device) is to achieve root and let it be. I don't want custom recoveries, kernel overrides or anything else other than having root. Thus my search on what will be be the best venue I have how to get the tablet safely rooted without messing with TWRP again or trying to mod the bootloader. And that's pretty much it..

And let me state, I have received nothing other than truly overwhelming support and help from lots of members of the community on my particular case for which I am extremely thankful and appreciative.