[Kindle Fire HDX 7" & 8.9" Q&A, Help & Troubleshoot] KilgoreTrout71:
Greetings, all of you who know better than to do what I did . . .

I could use some advice from someone who's been around the block with the HDX 8.9 Apollo, 3rd Gen. Kindle. For my part, I'm usually adept enough to avoid problems that should be foreseen, but I was outclassed by whatever was going on here, and I unwittingly dug myself a hole. In a matter of days, I went from having a mostly-stock, rooted FireOS that played nice with Google, to a device with weird quirks, to soft-but-hardening brick. And yes, I've been all over here, reading all kinds of threads. What I usually find is that my situation applies partly, but not fully, to the problems that have already been addressed here.

Back when things were good, the status was:

Rooted with Kingroot, replaced with SU, proper Safestrap installed, XPosed Framework running with the HDX module, seamless integration with Google, disabled OTA according to the instructions provided in the thread on that topic, etc. I had one strange incident where various apps were saying I wasn't rooted, so I repeated the Kingroot/SU process and all was good for several months.

Then suddenly, after the device had sat on my dresser unused for a few days, I picked it up and it started doing some quirky stuff again. Sorry, I can't be more specific than that, because I don't remember--except for one thing: instead of getting a message plainly indicating that I wasn't rooted, anything that sought root access seemed to either hang or crash. I thought it was that same mysterious problem again, so I attempted to do another round of Kingroot/SU, but I kept getting hangs and crashes. At that point, I was still able to reboot into the OS with no difficulty. Until one day, that hung too. Then I was in the same boat as many people here, i.e., "Kindle stuck at boot screen."

I tried all kinds of stuff that's been explained around here. I still had Safestrap for a few boots, but not enough room for a backup. After following some instructions to attempt a fix using the ADB/Fastboot environments, though, Safestrap disappeared. In retrospect, I believe that if I had gone straight to getting the system mounted R/W, I might have saved myself some grief. But maybe not. By the time I got to attempting that, all I got was "permission denied" anyway. Finally, I tried some of the brick recovery/re-root solutions offered here, and I managed to get one of them to wipe my system out, only to be told that it had no permission to write anything in its place.

So here I am: ADB/Fastboot access still intact, but no system, which means no solutions that involve shell commands. (I can still push files, so I'm wondering if I could push a shell in there or something, but I'm definitely out of my depth at this point. My bootloader is locked and I appear to have no root access. (The command "adb root" actually disconnects the device from my computer, so I have to start-server after that, and I don't know if it comes back with root or not . . . but I think it's safe to say, not. I can't seem to do anything that requires special permissions.)

So . . . now that I've exposed myself as a complete turd, is there anyone out there who might have some advice that would lead me in the direction of reviving my Kindle?

I'll keep an eye out as often as I can--got some pre-holiday craziness with my work schedule, so I'll address any responses ASAP.

Thanks!

KT71