[quote="takarada"]Sorry, I didn't see the other post.
So it is a known problem if the drive is connected after DO is started[/quote]
That's one theory that some people have, but it isn't like that for everyone and I don't think GPSoft have ever been able to reproduce it. Opus 9 has some changes which should help in this area but it seems, from threads like this, that some USB devices (or USB filesystem drivers) still cause the problem sometimes.
The best way to help solve it is to go through the debug steps in the FAQ and report back what you see: