WinXP sp2. I burned to disk some family photos using Microsoft windows highmat, but now windows cant open them ! I tried IrfanView who says they are a JPG file with the an incorrect extension but cant Rename files. The pictures IrfanView give are very small(nearly thumbnail) to be sharp & clear. When I increase size (640 X 480) they are very blurred. Is there any posibility of some other free software who can rename the file so as to get a proper normal clear picture please ?