Question : Problem: How to get Remote Assistance working with Routers / Firewalls in place?

Hi-
I seem to be Tech Central for my friends and family - would like to use Windows Live Messenger's Remote Assistance to take control of their machines remotely - but never got around to figuring out how to get it working with those people that have a router or firewall in place.  What configuration changes do I need to make to get this working?

Answer : Problem: How to get Remote Assistance working with Routers / Firewalls in place?

The problem is only if you also have a router. Basically using remote assistance through Messenger only works when just one of the participants is behind a non UPnP router. If both the "expert" and novice are, then it won't connect.
http://support.microsoft.com/kb/301529

So for me, when trying to give remote assistance through messenger to a user with a router I temporarily add my computer to my router's DMZ.