Exchange Server 2007 as Proxy for Exchange Web Services

With my new MacBook Pro and Snow Leopard, I would like to connect to my Exchange Server at home. Apple’s Mail program supports the connection to an Exchange Server 2007 SP1, but not to its predecessor, unfortunately.

My infrastructure at home is pretty old, but still functional. I. e., I still have an Exchange Server 2003 which does its work (family calendar, RPC over HTTPS, OWA, OMA, ActiveSync). What I miss now, is the access from my Mac.

Since Exchange Server 2007 requires an x64 architecture, I installed a Windows Server 2008 x64 as member server on a virtual machine using parallels on my MacBook Pro. Unfortunately, it’s my only Computer at home with a 64-bit capable CPU. More precisely: where I can install virtualized computers with a 64-bit OS.

The new virtual Server on the MacBook isn’t always on. Of course, with such a setup I don’t want to move any mailboxes off my Exchange Server 2003 which is based on real (32-bit) hardware and always reachable. Thus, I installed Exchange Server 2007 SP2 in its Client Access Role on the virtual server. I thought, this way I could gain the access to Exchange from my Mac, because the Exchange 2007 Client Server provides the Exchange Web Services needed by Apple’s Mail program.

Badly enough, Apple’s Mail program didn’t connect to Exchange. Reading TechNet’s documentation, I found out that proxying from a Client Server to an Exchange 2003 Back-End-Server doesn’t work for Exchange Web Services (see

The following scenario illustrates how incoming requests are handled for a user who connects to an Exchange 2007 Client Access server named CAS-01 by using Exchange Web Services.

The Client Access server queries Active Directory to determine the location of the user’s mailbox and the version of Microsoft Exchange that is installed on the Mailbox server. If the user’s mailbox is located on a server that is running Microsoft Exchange Server 2003, proxying cannot be performed and the request will fail. If the user’s mailbox is on a server that is running Exchange 2007 Service Pack 1 (SP1), continue to step 2. If the user’s mailbox is located on a server that is running the RTM version of Exchange 2007, the request will fail.

This means that if I want to connect my Mac to my Exchange Server at home, I will need to upgrade the whole infrastructure: buy new 64-Bit hardware and fulfill the migration from Windows Server 2003 and Exchange Server 2003 to Windows Server 2008 x64 and Exchange Server 2007 or 2010 x64.

Or, I buy Microsoft Office 2008 for Mac.

For the meantime, I will keep using Outlook on my virtualized Windows PCs within Parallels.