www.makemkv.com

Since yesterday I get the following (similar) messages when trying to read BD's:

HARDWARE ERROR:LOGICAL UNIT HAS NOT SELF-CONFIGURED YET' occurred while reading 'BD-RE TSSTcorp BDDVDW SE-506CB TS00' at offset '524288'

After a few of those messages, MKV stops reading and says Failed ot Open Disc.

Any idea was happened with here?

Most likely scenario is that there is a communication issue between the operating system and the drive. Getting the hardware to reset usually fixes these.

The most reliable way to do this is the shut down the machine completely (power off), then restart it. Just rebooting won't always send the reset signal to the hardware, but power-on does.

Thanks, problem solved.