I was called to fix the entourage connectivity issue to an exchange 2007 farm on a weekend and hence thought of sharing the info!
First things first, both entourage 2004 and 2008 will work with exchange 2007. But, it doesn’t work out of the box. There are a few things you need to configure as an exchange admin.
Entourage uses webdav to connect to exchange 2007, pretty much in the same way OWA 2003 works. That means, entourage accesses /exchange and /public virtual directories. By default, webdav is not enabled on an exchange 2007 server.
Exchange 2007 CAS On Windows 2003:
If your exchange 2007 CAS server is running on a windows 2003 server, Webdav has to be enabled in the Web Extensions section in the IIS snap-in.
Exchange 2007 CAS On Windows 2008:
If you have your exchange cas server running on windows 2008, you need to download and install the webdav package to begin with. Download it from here
Installation is pretty simple. Once installed, it has to be enabled for default web site in IIS 7 snap-in.
Make sure that authenticated users have access to the Client AccessExchweb directory, which is in your exchange 2007 installation folder.
In Entourage 2004, you need to specify your exchange server as either casserver.internaldomain.local/exchange/primarysmtpaddress or mail.domain.com if you have split dns. Public folder server should have the format casserver.internaldomain.local/public or mail.domain.com/public. Modify the urls depending on your network.
Entourage only connects to CAS servers and the urls should reflect that. By default, entourage picks up the netbios name of the mailbox server when trying to setup the account automatically.