If any of you installed the Microsoft update titled KB951748, then you may experience Internet problems thanks to a clash between Zonealarm and this update. To fix the issue you can either uninstall the update, change your firewall settings to medium, or switch to another type of firewall. To uninstall the update, do the following:
1) select "Start->Settings->Control Panel"
2) select "Add/Remove Programs"
3) select the 'check' box at the top of the screen that says "Show Updates" (there may be a pause for a minute or so)
4) scroll down the update list until you see the update that says "update for Windows XP KB951748"
5) Select the "KB951748" update and click on REMOVE
Just thought I would warn anyone who didn't know.