It was working normally, and it was last successfully upgraded to a custom rom and CWM 220.127.116.11 a month ago.
The custom rom was (to my best knowledge Android Revolution HD 11.2 - 4.1.2)
Booting into recovery and download modes works.
CWM recovery works partially. Erasing Cache en resetting to factory works, and sometimes results in getting to the second splash screen of the boot process where it again gets stuck (Samsung animation keeps glowing), but more it keeps getting stuck at he first boot screen.
Erasing Dalvic cache leads to immediate reboot.
CWM log files cant be opened / external sd card can't be reached/mounted.
So CWM is only working for a small part.
I've attached images of the CWM screens including a log-screen that shows that files and folders cannot be found.
Using ODIN, to flash a new CWM or custom/original ROM result in a FAIL message.
Tried different ODIN version, two original Samsung data cables and two computers. Alle the same result. FAIL.
I'm hesitant to continue now without some help. I might do more harm and destroy all chances there are to recover this tablet.
I've flashed all my phones and tablets before. I'm not an expert, but never had a mishap, because I triple read the instructions. The situation that arises now is not a result of a failed upgrade/flash, but suddenly appeared one morning.