error opening file in Photoshop 5.5

I have a student who has many files that she saved as .jpeg in Photoshop 5.5. She is unable to open about half of them and gets the following message. "all the files in the folder cannot be opened by Photoshop or have mismatched color profiles." She is using an iMac with system 9.1. Does anyone know what is causing the problem and if there is a way to fix the files? Thanks.

If they won't open I would think they are corrupt.

she could try Graphic converter.

or

if they are rgb ImageReady