I am having an issue with setting a firewall policy. I am trying to create a policy to allow remote access to the ISA server for administrators. I have done this but it only works if I set the USERS section to 'ALL USERS'. I tried to set it to 'all authenticated users', myself or a domain admin and it won't work.

You need to edit one or two predefined System Policies to enable Remote administration for ISA Server. The steps are described here in a very instructive and clear way. The article addresses MMC and RDP access. ISA Firewall Quick Tip : Administrating ISA Server 2006 Remotely Using MMC and Remote Desktop Connection http://www.elmajdal.net/isaserver/Administrating_ISA_Server_2006_Remotely_Using_MMC_and_Remote_Desktop_Connection.aspx While ISA/TMG to some extent is an extension to Exchange, there is a dedicated forum for these types of questions: Forefront TMG and ISA Server A forum for the discussion of general issues and ideas regarding Forefront Threat Management Gateway (TMG) and ISA Server http://social.technet.microsoft.com/Forums/en/Forefrontedgegeneral/threadsMCTS: Messaging | MCSE: S+M