Can't start video function?? but everyelse works great

For some reason I can't get my video to work. My webcam works fine (I
can use other programs to video conference). But for msn, I would
click the video button, then msn would pause and then crash...

I have a sony all-in-one computer. the model is W1. it's a 2.8, 512
ram unit. i have a wireless router, but that's not the problem beacuse
i can start video conversations on other computers on the network.
please help

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