Hello guys.
I have a big problem. 3Days ago i flashed a new file on my a6 4f 3.0tdi. All works great, but today i tryed to flash a new file with kess,galetto,mpps ans always security code error. I cant read, write and i also can't do an id.
So i made a Backup with BDM K-Tag. I flashed with k-tag the ori-obd file and my car, but it wont starts.
All again, i flashed the last working file an see the Softwarenumber is YYYYYY. whats that?
thx for Help.
Best Regards,
Steve

lol, OBD read is only maps area, if you wrote that into the flash, good job, you bricked it.
SK error is very common on this ECU if tools don't have 100% correct seed/key algo for the ECU. It is enough to leave ignition on for 20 minutes and then retry.

If you really did make a full BDM backup before you bricked it, just restore the backup and it will be fine.