Error 1017. Router problem?

[myp99acct]

Sorry if I've posted in the wrong subforum.

I get error 1017 when attempting to log in to any server. Please help.

I have:
Followed install instructions perfectly
tried updating router firmware, linksys router
tried turning on/off router firewall
tried turning on/off router uPNP
tried turning on/off router DMZ
tried forwarding all ports
tried bypassing router and directly connecting to PC
antivirus and windows firewall are disabled

I have windows XP service pack 2
I remember steam used to have a problem where people could not play with newer versions of their router's firmware. I wonder if that's the problem here.