[Samsung Galaxy J7 Questions & Answers] anthonyloprimo:
Just for the record, I've noticed a trend. I always seem to encounter the devices that are the exception. Simply easy task for <insert device here>? Not for me. Quick and easy root or hack? Not for <insert device here>. Do I find a universal macguffin for a series of models my thingamabob is part of? Awesome. Doesn't work with mine, that's version 205205 of a 205200 series of thingamabob. ...I can't win.

Alright so now that I'm done with that silly little rant... I'm here with a new phone (and a new account... I think. I remember registering a while back for help with a Boost Mobile Galaxy Prevail but I couldn't log in.. all well!). I'm going to give as much detail as I can so hopefully this will help. If it's too much, sorry!

I have a Galaxy J7 (SM-700H), and I'm pretty sure this is the 2015 version. From some research I've found that the speaker vent are the two horizontal slits on the LEFT side of the camera lens, with the flash on the left side as a rounded square, vs the newer model's more ovalish rectangular shapes (and swapped positions of the LED and speaker). Additionally the default device name was "Galaxy J7" vs "Galaxy J7 (2016)". So unless there are other factors that might make it another model... I dunno.

I had first found a thread ( https://xdaforums.com/galaxy-j7/how-to/how-to-root-samsung-galaxy-j7-sm-j700h-t3235507 ) which I thought might help. I followed every instruction... to no avail. Odin3 runs and does in fact appear to work (yes, running as administrator under Windows 7 as well). The samsung drivers are installed. Odin says PASS upon completion, and everything restarts.

Now I saw some varying steps across videos. Some seemed to let the phone boot and fully start, then turn off, and press/hold the Vol+, Home buttons, then turn on the device, others doing this while removing the battery before it starts up fully at the initial logo (which my guess is to trick the device into needing to perform a recovery, like tricking Windows into Safe Mode). A video of this is found here: https://www.youtube.com/watch?v=j7NQXXFmYbE

Unfortunately, it does not boot into TWRP. It has the same general android menu, WITHOUT the ability to update from zip. It lets me update from SD card or from ADB, but not from the zip (and trying to mount internal storage if that was what I read correctly does nothing, either).

I tried with the most up to date versions of Odin, TWRP and SuperSu binary zips, and nothing. I tried branching off to use ADB, and that does not work, either. When I do that, I get the following errors:

E: failed to verify whole-file signature

E: signature verification failed

Installation aborted.

I tried unzipping supersu and just installing the adb from the file browser in android, and it installed but gave me this error: "There is no su binary installed and supersu cannot install it".

That said, during my initial research into rooting my device, it involved turning off fast boot from the battery settings. There was no such setting available at the bottom of that screen, just the option to toggle battery percentage.

Developer Options are active. USB Debugging was on. OEM unlock is enabled. USB Configuration has been set to MTP for whenever I do backups of the phone to my PC...

What on earth have I been doing wrong, or have I somehow obtained the one variation of the J7 that's un-rootable? Has my bad luck with the odd-device-out stricken again? Have I dun goofed? Or is there some other odd thing to try?