Image thumbnail and image different

I've been scanning some images via Photoshop and editing and saving (in file
number order) and on a few of them the thumbnail image in the folder is not
the same as the image itself. Double clicking on it opens up the correct
image. On each case the incorrect thumbnail being displayed is that of the
next image file (in number order).

Is this some form of XP display problem?

I'm using XP, Office 2003, Photoshop CS

Many thanks


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