Windows Live Messenger d/c's my Network

Hi people,

I am having a very annoying problem and I hope someone here may be able to help.

Everytime i install and try to connect to 'Windows Live Messenger', it manages to disconnect my Netgear Routered network from the Internet.
I have a Motorolla Modem connected to the internet and running through my netgear to my computers in the house, the Modem and net connection remain stable but the netgear almost blocks the connection from my P.C.

I have tried using alternative messenger applications, such as Pidgin and Trillian to get around the issue but the exact same problem occurs with them also.
To reconnect my system to the internet i have to simply restart the netgear, but when i attempt to run the messenger applications again i get the same problem every time.

Can ANYONE at all help in anyway, it would be greatly appciated.

Kindest Regards
Matt Marsay