Right click on drive bar

if you click right on drive bar d.o. closed all the lister and itself

If you right-click a drive while showing My Computer in Opus does the same problem happen?

If not, or if you do it in Explorer and it works okay, is there anything "unusual" in the menu that appears?

Problems like this are usually caused by a 3rd party program adding something to the context menu which breaks inside Opus.

I'm not sure if it has any effect on this particular menu, but it might be worth a try to turn on Preferences / Miscellaneous / Windows Integration / Hide Windows items on file context menus.

Anyway, if you can narrow down which program/item is conflicting with Opus, I'm sure GPSoft will look at it and create a fix or workaround for the problem, whether it's a bug in Opus or the 3rd party program doing something naughty (which is often the case with context menu programs, for some reason).

Thank you nudel,
I think that there isn't any 3rd part program that interferes whit d.o., infact, untill rel 8 all works very well

Anti-virus tools and search tools often add things to the drive menu and some things have handlers which are queried for all menus (and decide at the time whether to add items), if that's any help.