It isn't my computer, per se, but my connection. I'm not sure how this happens, but I often find that my internet connection just stops. We're still connected downstairs, but none of my browsers will load. Usually, I'm forced to having to restart my computer to fix the problem.

Does anyone know what might be causing this?

It happens to me all the time too, im not sure...

make sure you have downloaded all the service packs for each computer... I hasd that prob not too long ago, and that's what the microsoft tech told me, and it worked?