Command and Conquer: Yuri's Revenge Network game not working?

[TheChipmunkMaster]

I have Command and Conquer: Yuri's Revenge and I was trying to play a networked game. One PC runs Vista and the other runs XP with Service Pack 2. My computers see each other in the network lobby and the part when you set up the game (where everyone picks spots to start at, rules, etc.). At the bottom, it says the map will be transferred at game start. We start the game and then the game goes into a black screen. The music plays, but that's it. It was fine a couple of weeks ago and all of a sudden it just stops working. Please help me, I would like to play with these two computers again!