Help cd copy

[mex]

Help

I have done a back up copy of who wants to be a millionaire when I tried to run the copy it comes up with error (1500 another installation in progress. You must complete that installation before continuing this one). I have installed the CD once already but then uninstalled it. I have checked the registry and the program files but there is no trace of the program. Even if I try to load the original copy it still comes up with the same error code

Any ideas or help would be much appreciated

THANKS