XYplorer Beta Club

Use XYPlorer every day.
It deals with my 400,000 Images, searching, sub sets etc.

This occurred all images apparently damaged (In this folder only)
YET, when I click on the damaged image, the correct image appears.

Any fix?

PS: Windows 7 OS (All images undamaged when viewing with ACDSee)
Shut down, reboot no fix

UPDATE : All FIXED (Refresh Thumbnails did it! )
Love my XYPlorer, most important part of my hobby, could not do without it

Thanks