The game is not compatible with Windows 7. This is the StarForce copy protection used. The installed system driver of the copy are not compatible with Win7, they are automatically disabled by the system. Also updates are not possible because the used StarForce version will always mitgliefert with the respective game and no upgrade is possible.
The system requirements "Windows XP, 2000 (exclusively)" are therefore to be taken literally. No upward compatibility.
So if you only Win7 is available, the game can save.
Exception could be the XP Mode offer Professional from Win7.