Ubuntu behind ISA SErver 2004

Recently we have installed ISA server 2004 and my ubuntu system is behind it and am not able to connect to the internet.  Please let me know how to browse internet behind the ISA server 2004 on windows server 2003.  I am very new to ubuntu and want to learn things.Any help and guidance will be appreciated.Thanks in Advance

Similar Problem

I have a very similar problem...  Though I got internet access to work just fine.  In Firefox, go Edit > Preferences > Advanced > Network and click settings to change settings to connect to the proxy server.  You will be prompted for your network credentials.The problem I'm having is with using Synaptic to get updates and whatnot.  I'm a bit of a n00b, but I've been searching and I've tried like 5 different ways to change proxy settings, but nothing is working!I've tried setting the network proxy under System > Preferences, I've tried using the settings in Synaptic, I've tried several different ways of setting up apt.conf and I can't get it to work.  I keep getting "407 Proxy Authentication Required"