Kilroy12

I purchased a retail copy of Theatre of War several years ago and had it installed on my desktop. Recently I attempted to reinstall the game but am unable to launch it because I am getting an error when I try to activate the licnese on the back of the box. It says that I have used up my alloted activations and need to unlicense the old install before I can use a new one. The problem is I have gone through two different versions of windows in the time since I last used to game and those installs have been gone for years. Is there any way I can get around this so I can use the game that I paid for? Any help would be greatly appreciated.