

Have you moved your old save to another folder, un-installed and the re-installed CM4 then put your saved game back and it won't work?
The reason your saved game wont work is that CM4 only creates a UserData folder when you first save a game.
1 Start a new game and save it (which creates a UserData folder) then copy your old save to the UserData folder
2 Just create a UserData folder in your CM4 folder, and put your old save into it.
There's two ways of fixing this problem, the first I have done successfully and the second I have not tried yet but it should work
e-mail: CM4 Solutions