iCal won't open "because it may be damaged or incomplete"
Hi - I am attempting to fix a problem with iCal. I am running the OS 10.6.8. The problem is that whenever I try to open iCal, it simply comes back with "You can't open the application My Calendar because it may be damaged or incomplete". (sidenote, if iCal and My Calendar are different, let me know...I'm a windows user trying to fix an apple). I've tried clearing the caches and multiple restarts to no avail. Supposedly, the problem first arose after updating the application.
What I would prefer to do is to use the installation disc to re-install the app, but I cannot find the disc anywhere. Is there a different work-around that can be done, or am I just out-of-luck because I can't find the disc? I very much doubt the existence of a recent back-up recovery point, but if you could point me in the direction of that info, I could look into that. Other than that, any and all help is more than welcome.
Thanks much for your time!
Mac mini, Mac OS X (10.6.8)