Illegal operation performed.

I was using office 97. An excel sheet when used for a print threw an error “illegal operation performed”. I removed and re-installed office 2000. The same error was displayed. This excel sheet when used for a print on another machine having office 97 & 2000, printed without any error.What can be the problem.? Also how do I tackle “the file is read-only and locked for editing. Please click notify….”.?