It might help if you put these files in a public folder location, or make sure the properties of the photo are set to everyone to have full rights to them,
But in wlpg a public folder might just be as good,
But keep in mind windows 7 will try to protect your system from files from other computers,
If you go to internet options, and then advanced tab, scroll down to the security section, check the box to allow active content from cd's to run on your computer.
Odd place but it might help ?