Replying to ZIP DRIVE HELP!!!!!!!!! +K for first answer that works....

Okay, I made a Keynote (Mac version of Powerpoint) presentation for my AP US History class. I transferred it onto a Lexar Drive (small, portable, USB drive) and took it to school. When I tried to open it on multiple school computers, it said something about an "alias" problem and it would not open. I need to solve this problem by tomorrow morning so I can present. Anybody know what is wrong?