I've had this problem before with ISA 2000, and was hoping it would go away when I switched to 2004, but it's still there. When trying to play a streaming video (video.msn.com for example), I get a gray login box for the proxy server. If I enter the usual DOMAIN\username, and password, it will let me through. If I cancel that login, sometimes it goes through anyways. I have ISA2004 installed on a W2K3 server, using Windows XP as a client, Firewall Client is installed, proxy settings are in use in IE, and there is a Streaming Media rule in place. Looking at the real-time firewall log, it appears that it IS hitting the Streaming Media rule, but is getting denied. This is probably due to it authenticating as Anonymous, and that rule requires people to be in a specific group to have Streaming Media privileges. How would I get this to authenticate properly without people having to login every time they go to play a streaming video?