an image directory, will display the files as thumbnails in a single row at the bottom of the screen and a currently selected thumbnail as a much larger image on the rest of the screen. All the files will usually not fit, so 'panning' must be done to bring other thumbnails into view.
The directory (or folder) must have a particular property before film strip will be available for selection as a viewing option.
There is also a small database called Thumbs.db which stores the thumbnail images. I'm wondering if this database is corrupted. You normally do not see Thumbs, but, if you reset the folder property so that hidden files are seen, you will see it.
A quick test would be to set up a new subdirectory, and copy some image files to it. Then view it in explorer in either thumbnail or filmstrip mode. If you can see the images, then you know the problem is a corrupted thumbs file. If you still can't see it, then whatever Windows uses to view common picture formats like jpg and tif has been impaired. It may indeed be necessary to reinstall Windows to get this function back if it is damaged.
However, the person is getting a no preview available message. This probably means that Windows can't read the file as a known image file type. We do need to know, after a thumbs problem is eliminated, what type of files these are, and what is creating them. For example, Windows cannot display a Photoshop PDS file. It doesn't know how to read it. Also, the file may be damaged which would prevent Windows from reading and displaying it.