slow database conversion rekordbox 5 to 6 failed

I tried to convert my RB5 database to RB6 (6.0.3). About 24000tracks (135GB) (with ROG strix PC with WD10, After 75hours and progress still at 32% I decided to discard, RB prompted if I want to continue conversion when I open RB6 the next time and I choose "Yes".

Now when I open RB6 again prompts to convert or start with empty database. It does not matter what I choose, rekordbox is not responding...

It looks like I cannot use RB6 anymore on my PC...