Fully exit Opus (via File / Exit Directory Opus) then re-launch it. Is the problem still the same?
Does it affect all folders, or just some?
It's possible the thread that requests the information is getting stuck on one of the files. (Most often this happens if the information is requested for a video file, which triggers a video splitter DLL that then gets stuck in a loop on that particular file. Updating the involved splitter can often fix it.)