Replace Microsoft Photo icon with thumbnails.

[Denis DellaLoggia]

Somewhere along the way, my many hundreds of photos lost their real thumbnail to the photo icon. I need the thumbnails back! Searching for a photo without the thumbnail takes ages.

 

[Bastet]

Try these:
Reset thumbnail cache:

https://www.tenforums.com/tutorials/5655-clear-reset-thumbnail-cache-windows-10-a.html

Or: Rebuild icon cache:

https://www.tenforums.com/tutorials/5645-rebuild-icon-cache-windows-10-a.html

 

[Grizzly]

this may help too: