[Xperia Z2 Tablet Q&A, Help & Troubleshooting] Marmalade_Shaws:
Hey guys, please forgive me for any bad etiquette or lack of information (any information I can provide is available upon request if I leave anything out). I am new to forums in general and especially to XDA, which seems like a good place to get help.

I recently purchased a Sony Xperia Z2 Tablet from Craigslist under the assumption it was a fully unlocked tablet not associated to a carrier. Turns out it was a Verizon Z2 tablet. I dislike Verizon with a firey passion and without getting into too many details, I'm fairly certain they won't help me because a) this tablet wasn't purchased through them as a customer and b) Verizon and I have bad history (unauthorized account modification, shady charges, etc.)

So I thought I'd do my best to make the tablet mine since the asshole who sold it to me has ceased all contact and I don't know how to get a hold of him anymore. No receipt and a data-less tablet.

Anyway, I successfully rooted the tablet and began installing apps that I installed for my G4 when I rooted it (SuperSU, Adaway, Greenify, etc.)

Things were going well but I realised I wanted anything that had to do with Verizon removed from the tablet so I was going to flash Cyanogenmod onto it with a guide I found online. Now rooting and installing custom recoveries was familiar territory and I did these flawlessly. It had TWRP and I made a backup of the system -no Nandroid, sadly-and I began the flashing process. The process said it completed without issue and I went to reboot my device. Enter my current situation:

The device, when I attempted to turn it on, all it did was vibrate constantly until I let go of the power button. Attempting to enter recovery mode (green LED, power + vol down) it showed me, instead of TWRP, a very basic recovery mode with basic options. "Continue booting up", "enter safe mode", "system recovery", and "power down". I tried entering safe mode and it just shut back down, I tried doing a system recovery and it shut down. The only time I ever see the "SONY" logo is if I'm entering this mode. I can enter what I assume is "fastboot mode" (power + vol up and plugging the device into a PC). Nothing on the screen but the LED is blue. I am trying to find guides to restore it if I can and it all looks promising but the only things I know how to really do are root and install custom recovery. I know there are PC tools I can use to send commands to it while it's in fastboot, or send commands in general I just don't know where to begin.

Does anyone know how to fix this? I know it was from Verizon, which sucks, and I know the problem most likely occurred with the attempted flashing of Cyanogenmod. I think I read somewhere I might have done something regarding mismatching kernal numbers. I couldn't find a way to unlock the bootloader so I assume that had something to do with it too.

If someone could give me a guide to restore it to at least its stock ROM where I can begin rooting and installing a custom recovery again, that would be great. Even better would be just flashing a ROM on there that doesn't need Verizon or being able to take it to a stage where it's unlocked and the only evidence it was ever with a carrier is the Verizon logo on the back. I'd really hate to think I wasted money on this and now I'm at a dead end because of a mistake I made. This was supposed to be a gift for my mom on her birthday which is coming up soon. So if anyone knows anything, or has a guide where we can at least get the thing bootable again and I'll just try and deal with a rooted locked device, that would be great.

Thanks for considerations,

Marmalade_Shaws