Why in my pictures folder do some of the thumbnails show the picture but then some are blank

Question

when i go to my pictures folder there are alot of the thumbnails there that are blank and then some show the picture, but if i right clcik on one of the blank ones and select preview then you see the picture and then if you select print option when the printing wizard box comes up you see a whole different set of pictures(like there not all in the same place) would'nt any picture i have saved by selecting "save picture as.." be in the same place ?

Answer 1

Different picture types could be associated with different applications. That's a cause.

In other words, I don't think Windows is set to handle the pictures /file types you can't see thumbnails from.