After doing some research, I discovered that a number of people encountered the same issues after installing a recent batch of MS updates. Several victims have pointed the finger at their firewalls. At the time that I first encountered the issue, I was using PC Tools Anti-virus software and the XP firewall. I disabled both and tried to access the net again, but to no avail.
I have uninstalled the Anti-virus software (been meaning to replace it anyway), reinstalled my browsers, triple-checked the proxy settings, and even tried a revert back to before the update was installed... still, nothing has changed. I tried to troubleshoot the issue through Microsoft, and on the forums, but no one was of any help.
If anyone has any idea of what the heck is going on and how to fix it, I would be most appreciative.
P.S. I have done several virus scans, all of which have come back spick-and-span. I have had no other indications of virus activity, so I'm not sure that's the problem either. One other thing of note: around the time of the MS update and all this started, I was trying to access the net and my system inexplicably prompted me to re-enter my network WEP key. Don't know if that's related in any way.
Edited by The_Dude, 19 August 2010 - 11:22 AM.