[Samsung Galaxy S7 Questions and Answers] kettir:
Phone: international s7, g930fxxu1apb4, build mmb29k.6930fxxu1apb4. Purchased on swappa 2 weeks ago.

What I did: I was using Good Lock. I decided I didn't like it very much and instructed Good Lock to uninstall. The s7 said "this will replace the software with an older version" and I said Yes. After that, bootloop on every startup. I've tried factory reset and wiping cache from recovery mode. I've looked for the official ROM in the hopes of flashing it but haven't found anything except sammobile and they want a membership fee just to download, otherwise it will take literally hours (according to their site). If there is a direct link elsewhere I would love to know about it. I have the latest Odin installed and the drivers on my PC.

Current symptoms: bootloop on startup - First I get a blue screen that says "installing system update" and then the system starts booting and eventually I get to the "breathing" SAMSUNG and it stays there forever, just "breathing".

I can boot into download mode; At the bottom of the screen is "supported API: 3" and "dm-verity verification failed..."

Selecting "Update from SD card" or "update from adb" gets "updated from external storage is disabled."

"Wipe data/factory reset" seems to go without an error; I get formatting /data, formatting /cache, set factory reset done, coping media files, preload checkin, and finally data wipe complete.

"wipe cache partition" gets wiping cache, formatting /cache, cache wipe complete, cache wipe complete (it does say that last one twice).

"mount /system" gets mounted/ system.

"reboot system now" starts the reboot process and goes into the bootloop.

I can hold down volume down and power and restart the phone. At that point if I'm quick enough I can get into download mode or into recovery mode.

I have flashed the proper version of TWRP via Odin. However, it doesn't seem to "stick". Not sure if that's because I do a cache wipe and data wipe or if it's just something I don't know about. But right after flashing, when I go into recovery mode, TWRP is there. Later it's gone.

I found the following about a Note 5 having this error but of course I need the official firmware to try this fix. Step 3 involves a tar.md5 packager which I have downloaded.

1. Download official firmware for your device from sammobile

2. Extract your firmware files from the TAR. (delete ext .md5 from file name, then open with 7zip/winrar. unzip)

3. Repack your firmware AFTER deleting cache.img.

Put your ROM.tar.md5 into folder \in, or put parts of rom into \parts, run TAR.MD5 PACKAGER

Select option [3. Extract ROM] - for extract pars of rom into folder \parts

Select option [1. Make TAR] - for packing CSC.tar

Select option [2. Add MD5 to TAR] - for convert .tar to .tar.md5

4. Flash the repackaged firmware via ODIN

I would be willing to give this a try if I can just find the proper ROM to flash!

Is there some way to get assistance from Samsung in getting the software to flash?

I'm definitely interested in some expert opinions on this. If I can't fix it myself I'll take it to a shop nearby and have them give it a try (presumably they have the special hardware I don't have.)

Thanks in advance for any help. Anyone who helps me get this thing working again, will get a super special mention in my prayers when I go to church this weekend, plus I will buy you a beer if you have a Paypal. Beer AND blessings, such a deal. So all humor aside, please help. Thank you!