So you bought Company of Heroes or Company of Heroes Opposing Fronts? The vanilla CoH comes with 1.71 patch cd, which includes DX10 support. The current CoH patch is 2.301, SO you would have to patch a LOT if you wanted to play it. But if you plug off your internet when you are starting the game, it will ask you to insert your dvd, you do that and then it verifies it and then you will be able to play skirmish.
http://cohpatch.relic.com/ From there you should be able to DL your patches. This game is a bit tricky with these patches but you will get used to it :)