In a museum we have 3 android tablets, 1 Samsung tablet and 2 commercial tablets. The tablets don't have internet connection, wifi is disabled, bluetooth is disabled. the tablets auto boot when power gets on, and autostart a fullscreen application to play video's.
A few weeks ago one of the tablets was missing his video files (stored on the external SD card). A few weeks later, one tablet was missing files again and the other tablet has the default videoplayer of android to play video files. After putting back the files everything worked again.
But this weekend, 3 android devices were not working. One commercial tablet is missing the video files on the sd card and
.fuse_hidden file was on the external sd card, the samsung tablet is also missing video and photo files, and the other commercial tablet is giving the message
Unfortunately, the process com.android.system.ui has stopped.
When I click ok the screen goes black and comes back with the same message. In the back of this message I see a unlockscreen, clock and text
connect your charger. So so strange. After clicking multiple times ok, the message disappears but I don't have access to the tablet, because I don't know the unlock pattern, because I did not make that. On the external sd card no files are missing but a extra folder is there with the name
Are the tablets hacked? Is this possible offline? I am really frustrating about this, because I don't know what is going on. I hope someone knows.
Thanks in advance!