Windows XP Network Glitches

I recently upgraded to Windows XP. Occaisionally, when browsing in Internet Explorer, I start getting ‘This page cannot be displayed’ errors. Once this happens, no web page will display. The only fix I’ve found is to open my network connection inthe control panel, and click ‘Repair Connection’. Once I’ve done this, I am able to access websites again. Eventually, though, the same thing happens, and I have to ‘repair’ the connection.
Has anyone run into this before?
I’m running an Athlon XP 1900+, and my internet connection is AT&T Cable Internet (previously AT&T@Home) through a basic Linksys router. Other PC’s connected to the same router don’t have this problem.