Remote Assistance Unable To Send Connection Request

http://www.winforumz.com/windows/Remote-Assistance-connection-failing-ftopict584713.html (Remote Assistance connection failing)
Hi, My Dad is trying to invite me to use Remote Assistance but we can't establish a connection no matter whether we use Outlook Express or Windows Live Messenger. He's using: Windows XP Pro with SP2 Norton Internet Security 2006 Windows Firewall is off Zyxel Prestige 600 broadband modem I'm usin..

http://www.winforumz.com/windows/Remote-assistance-connection-established-ftopict600830.html (Remote assistance connection cannot be established)
I'm at a loss here, I'm trying to connect remotely to my mother-n-law's computer and it tells me the connection cannot be established. I have walked her through disabling firewalls, I have edited the ip address in the email, and nothing seems to work. I was able to get on her computer before, ..
« She is also using a sprint dsl modem »
« Are you or your mother-in-law behind a router? If so, make sure UPnP (Universal Plug n Play) is enabled on the router. Also run a scan disk or error checking on the C: drive for each computer. .. »

http://www.winforumz.com/windows/Remote-Assistance-connection-established-beca-ftopict613284.html (Remote Assistance connection could not be established beca..)
I am trying to help my Mum with her PC Both PC's have XP Both PC's have Windows Firewall Exceptions BUT... when I accept the invitation from my mum I get this message "Remote Assistance connection could not be established because the public key provided in this connection request did not match."..
« am just guessing here, in case it is the prog you are using maybe try this one ?? »