Ok i'm using the latest version of windows live messenger at the momment, and so far i can call my friend that doesn't live to far, but for some reason i can't call another friend of mines this happened friday after playing a video game. It crashed and the call ended and after that i couldn't call her back and vice versa.
During that time i was using windows7 but switched back to vista. If anyone can help it would be much appreciated thank you.

Internet connection error on one of your sides.