Using Windows 2008 Server R2 as backup target on network

I'm trying to backup a Windows 7 disk image to a Windows 2008 Server R2 using True Image Home 2011 and it will not show up in the "network" when I look for it as a target. The server is on a domain and I can see workgroup computers that are not part of the domain. Any thoughts? I recall this working for Server 2003 but I did have to authenticate to the server once I selected it from the network.