How do I delete all content on Windows Fax and Picture Viewer?

It seems when I send myself a picture through a file in an E-mail, it always loads by Windows fax and picture viewer. But, besides the main picture being sent, if I hit the little arrows at the bottom, it seems like every image ever viewed on my computer for all time is also there! Whats up with THAT? Any way to delete? I HAVE hit the X delete button, but the next time I send a pic its right there again.