I no longer am able to view thumbnails for almost any of my Corel files, new or old.  I think files from a very old versions are viewable, but not from Graphic Suite 2020 or from my previous version 19.0 (2017).  I've done all the Windows stuff, making sure the right things are checked in preferences (ie that the "show icons only" box isn't checked), and I'm able to view thumbnails for other file types.  Is there a fix for this, as I'm wasting a lot of time having to open files to see if they're what I need.