JPG Attachment

Fram one day to the other I cannot open the Jpg attachments I receive from the same correspondent everyday. Using Microsoft picture & and fax viewer i get the message “no preview available. I tried to open the files received before and the same thing happen.
I tried to open with other programs but they do not work. I can use The picture & fax viewer to open pictures in “My Pictures”.
I have window XP SP2, and office 2003.
Anybody can help?