Problem with my xbox 360

[Wicked Grapefruit]

I have Splinter Cell: Chaos Theory, and I tried to play co-op online. It said it had to download an update, and reverted to the update screen for the original xbox. And then it crashes, saying "Xbox live is not responding. Please try again later". Weird thing is, it works fine when I play versus.

Any insight?

[Ninjavenom]

Ubisoft sucks at coding multiplayer online? The PA guys had the same problem with the last Splinter Cell game on the original XBOX.