VPN unable to connect to corporate anymore

I am getting an error 721: The remote computer did not respond when I
try to connect to my company computer through my VPN. I have a comcast
gateway and they said as long as I can surf the web, it is not their
problem. The IT guys at the company say it is a firewall problem with
comcast and they need to disable the firewall, meanwhile I am unable to
work. Is there anything I can do to fix this problem?

Please help...