what graphics card and how much ram do you have?
is it the complete edition of the game (the one that has the soviet campain in it)? If it is just the normal version then it will not work properly on windows 7. But I have heard there are unsupported patches that will make it work but these are created by people who do not work for the games manufacturer.
I have the complete edition and it runs perfectly fine on my windows 7 64bit system.
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