We just updated one of the computers in our office with the latest XP fixes.
Now, I'm having lots of problems connecting to the web, our local server, etc.
In researching the problems, I discovered I now have two firewalls: my original firewall package and now the Microsoft Security Center firewall.
I don't want nor need the Windows firewall.
I'm willing to even go back to the original OS configuration, if that is what it takes.