Strange slow response when browsing for backup folder

In setting up my PC with Windows 7, I have made a lot of use of the Backup/Restore feature in DOpus.

As I keep my data on separate drives from programs, a backup entails navigating to where I keep things.

DOpus takes ages to navigate to the location. Indeed, it shows the "not responding" message. It is responding, just takes a long time.

No other operation shows a similar delay.

Anyone else seen this? What might be the cause?

Could you post a screenshot of it when it's responding slowly or showing the "not responding" message?

I'm guessing that there's a slow device or slow/unreachable mapped network drive which Opus is trying to get information about to build the folder tree in the dialog where you browse for the backup location.