I've been using version 9.5.6.0.3937.x86 for several years (with XP SP3). I haven't had any significant problems until now.
The following bad behavior began recently, cause unknown.
If I right-click the toolbar, click "Customize", open the Command Editor, and click "OK", Opus closes. I don't even have to edit anything, just click "OK". Any edits I do make are not saved.
If I use FTP to navigate to my website, click "Rename" to rename a file, then click "OK", Opus also closes. Edits are not saved.
Bottom line - I'm no longer able to edit custom toolbar buttons or use Opus to rename files on my website.
No idea, given that I can't pin down exactly when the problem started. I do install applications from time to time, plus there are all the Microsoft security updates. I wouldn't be able to even guess at whether one of them caused the problem. I suppose I could spend an afternoon restoring disc images until I pinpointed the week Opus started misbehaving.
I understand that Opus hasn't changed. I was just hoping that somebody who's familiar with its inner workings would be able to connect the dots or might have solved the problem for another user.
The newest version of my password manager, Sticky Password, is causing the problem. When I close it, the problem goes away. I'll get in touch with the developer.