Looks like you need to talk to Comcast. Or tell more.
I recently had a Comcast Cable wireless router connected to my desktop (also have a laptop). Previously, I had just a regular Comcast cable box connection. I also connect to a VPN network (a university)for my Outlook e-mail. Prior to the installation of my new wireless router, I had no problems with my VPN connection to school - now that I have the new router - my VPN connection is unstable and I have problems getting on the internet - either very slow or not at all. As soon as I disable the VPN connection - all is well - even with my Outlook email (although I cannot then receive or send in Outlook). I have contacted the University and they say nothing would have changed on their end and the Comcast people say that as long as I can get on the internet, my VPN connection trouble is not their problem. I didn't have the problem prior to the new router box - so it has to be something with that box, I would assume. I have Windows XP with SP2. Would anyone have any suggestions. and thank you.