After mainly years of using DOPUS, I'm now having trouble with the file preview (viewer pane). I'm using the same keyboard shortcut I've used for years (CTRL-J); I don't remember if that's the default shortcut or I created it years ago. In any case, the preview seems to work OK (and relatively quickly) for Word files. When I try to preview a PDF file, the viewer pane opens but DOPUS hangs; I have to use the Task Manager to close it. When I previewed and Excel file, the preview showed up properly, but I couldn't move the cursor off the Excel file to another file. Again, I had to use Task Manager to close DOPUS. I had these problems with version 12.10, the latest version. Then, on the off chance that one of the betas would solve the problem, I installed 12.10.5 (beta), but that didn't help.
Not quite: The PDF files' previews do not appear in the preview pane in File Explorer, but the application doesn't hang, and I can move the cursor to other files. Similarly, the previews of Excel files do appear, and I CAN move the cursor to other files.
Opus doesn't display PDF or Office files itself, that comes down to the viewer components you have installed.
I'd focus on PDF first, since that seems the most broken, with it not working in File Explorer at all. If a viewer is having problems then it might leave the viewer pane in a state which then causes problems for other viewers, so let's get PDF working first, in both Opus and Explorer.
Which PDF viewer are you using? e.g. Adobe Reader, PDF-XChange, Sumatra, FoxIt, etc.
I would first try reinstalling the PDF viewer.
If it still doesn't work, try using another PDF viewer by a different company/author, and/or ask the people who make the PDF viewer you want to use for help. (It probably makes sense to focus on getting it to work in Explorer, since they'll be more familiar with that, and once it's working smoothly there, see if that also fixes things in Opus.)
I've been using Acrobat Reader, so I uninstalled it, downloaded it again, and re-installed it. That didn't help--and, of course, that didn't help with the problem with Excel files (I can preview an Excel file, but I can't move the cursor off of the file). In any case, I guess I'll try some of the other PDF viewers to see if they clear up the problem. I'll have to try that later, though, because I have a meeting that's about to start. I'll let you know if I still have problems with another viewer. Thanks.