refreshing scripts a problem

I'm having trouble with my php scripts running on my local machine. I'm running winXP, apache, and for the most part, everything runs ok. But sometimes the scripts will refresh rapidly for a few seconds, and then give up - "This page cannot be displayed." It seems to happen more often when I'm sorting a query that i had run in phpMyAdmin, and sometimes in normal scripts as well. Everything works fine on a remote server. Is there a setting I can change here? this is getting really annoying. any help would be greatly appreciated.