Thanks for trying that.
If you reboot into safe mode, does the problem remain?
If the problem is not there in safe mode, it's likely coming from a 3rd party component, such as a shell extension or hardware driver, which safe mode prevents from running. However, if the problem is still there in safe mode, then the problem could be something in your Opus configuration (e.g. a toolbar button which points to a network drive that is slow to access or unavailable, and which Opus tries to refresh when you change folders).
Depending on how safe mode behaves, there are more things we can try. I'll suggest some based on what you report back, but you can also see our list of general troubleshooting ideas if you'd like to try things in advance, or see if any stand out as possibilities based on your setup.