I can't play MM3! Earlier I played it for the first time for about 45 minutes, then got rid of it. When I tried to pull it back up, I got the message, "This program requires a security key. If you have one, select OK to enter it. After entering a valid key, you will not be prompted again." If you click OK, and enter the key, it says, "The key you entered is already expired. Please enter a new key."