[edited from follow-up]

I was able to fix the problem--thank you
Do you mind telling me what you did to fix the problem?

I think I had two different problems. First, I had changed permission on the medialab.exe program only and not the whole MediaLab folder. Second, I tried to give permission to a specific user and that didn't seem to work on our computers. So, I found out how to give permission to all users on our system and that worked. I didn't need to enter any codes after the permission changes--the program opened up correctly. Thanks.