[Android General] Froschface:
bricked?

Hello everybody,

I wanted to help a friend to flash a new ROM on his Kolina K100+ today... I am doing stuff like that for years, but today it went horribly wrong.

Now.. my friend wanted to update his phone with a new ROM. So at first I flashed a new recovery (ported CMW - from here) and installed a slightly modified stock-ROM (from here). However, after installing the ROM the first weird things started to happen... I ended up with a boot loop... and after re-visiting the recovery I was greeted with

E: Can't mount /cache
E: Can't open /cache

Well... after several unsuccessful attempts erasing or formatting /cache I switched to TWRP (ported - from here) which, interestingly, was able to format /cache. This allowed me finally to successfully boot the phone. However, I soon had to realize that the home button didn't work... after reading up on it in the internet I figured that several people had the same issue with the ROM I installed and suggested to reinstall it and wipe /data and /dalvik... so I did too. But the home button kept being unresponsive. At this point I decided to blame the ROM and went to look for an alternative... my friend likes the Samsung ROMs and we found a working port of the S5 ROM (from here --> WARNING: If you think about installing this ROM; do not install until you finished reading this post).

The new ROM installed without any problems through TWRP. Wiping /dalvik didn't take much time as well. But wiping /cache took the phone almost 15 minutes. Anyway... the ROM worked like a dream at first. After trying various features (does GPS work? does the home button work? does the status bar menu work? etc.) we figured out that the camera refused to take pictures because, apparently, there was no mounted SDcard available. Now, at this point I started paying attention to an error message that displayed in the notifications that said something like

/SDcard partition defect.
ormatting the partition may solve the problem. Do you want to format?

Well, it was a new ROM... so why not? However, after confirming nothing happened. The error message kept showing up in the notifications, the ROM still working almost perfectly. At this point we figured out that we couldn't connect the phone to a computer anymore (no file system visible). Of course I connected the two things and thought that maybe the ROM has problems formatting the partition and therefore I should do it manually in TWRP.

After booting into the recovery I was greeting with:

E: Can't mount /cache
E: Can't open/cache
E: Can't mount /system
E: Can't open /system
E: Can't mount /data
E: Can't open /data
...

Nothing can be mounted anymore. Through the TWRP file explorer I only have access to the very root of the system. This was, at first, surprising to me because the ROM seemed to work well before. Naturally I tried to reboot to see if it still works. But TWRP told me

No OS installed. Do you really want to reboot?

The next thing I tried was to format all partitions. Which failed, because TWRP couldn't mount any of them. Wiping Data (totally wiping the phone) also didn't work for the same reason.

Then I tried to reinstall the older ROM (the one that featured a non-working home button) via USB OTG. While TWRP showed me that the installation was successful, it also immediately showed me the error messages that /system, /cache, and /data couldn't be mounted or opened. A reboot is pointless because the phone says that there is no OS installed.

Next I tried to use fastboot to erase and format the partitions that can't be mounted... however, while fastboot recognizes the device, it gets stuck (waited for 60 minutes, no progress) at:

fastboot erase userdata
erasing 'userdata'...

This is the same for every partition, whether I try to erase or format single partitions or if I try to "fastboot -w".

Next, after googling and reading some forums, I tried to switch back to CMW (because somebody mentioned that this could be helpful). So I tried to flash the recovery with fast boot. However I got this error:

fastboot flash recovery recovery.img
sending 'recovery' (6010 KB)...
OKAY [ 0.203s]
writing 'recovery'...
FAILED (remote: partition 'recovery' not support flash)
finished.
total time: 0.234s

Installation of a recovery through SP Flash Tool does not work as well. The device is not recognized (Yes, I have the correct drivers installed, otherwise fastboot and adb wouldn't work).

As a last attempt, I then tried to flash a new ROM via adb. Again, just like fastboot, adb recognizes the phone without any problems and I was able to push the ROM onto the device. However, the installation went the same way as if it was done via TWRP (see above).

So now I am stuck with a phone that can only boot into recovery and bootloader but that is unable to access, wipe, or format any partition. I cannot change the recovery and I cannot flash any new ROMs, even though the phone is responsive to fastboot and adb. And at this point I am at the limit of my knowledge.

I only have two possible explanations for what could have happened:

1) The S5 ROM automatically encrypted the device and then something went wrong... leaving TWRP, fastboot, and adb unable to read, mount, let alone modify any partitions.

2) The hardware is damaged.

Does anybody here know a solution to this problem? It would not be nice to tell my friend that he has to buy himself a new phone.

PS: if anybody has the link to the Chinese stock ROM then please let me know. Although I don't think flashing it will work.