Yes, that is a domain login, type it in as DOMAIN\Username, and the password. When you say you're typing it in the address line, what do you mean? -----Original Message----- From: Mark Warren [mailto:mewarren123@xxxxxxxxx] Sent: Monday, May 02, 2005 17:00 To: [ISAserver.org Discussion List] Subject: [isalist] RE: Instant Messenger Blocking http://www.ISAserver.org Still having problems with Macintosh authentication. The Macintosh clients get an HTTP 407 Proxy Authentication Required. Access to the Web Proxy service is denied (12209). I have manually typed the IP number of the ISA server on the address line with port 8080 and connecting Normal selected. It does ask for a username and password. Is this a Domain username and password? There must be something I'm missing here. Mark Warren