I/o Error In Illustrator Cs2


I am using tiger and am attempting to use illustrator cs2, but get an I/O error when i open the program. I save my work on my HD and have attempted to delete prefrences and repair permissions, but the error still comes up. I have also tried to reinstall the program.
I also get this on several of my computers (though not all strange enough) but as far as I can tell it doesn't seem to do anything. Having said that, I think it has to do with looking for preference files in an admin account without the proper permissions to access them. i.e Student Users will get the message while the Teacher Users will not.