Santron, Also, I doubt that Windows 2008 R2 is a supported candidate for Exchange 2007 without service pack 3. Refer the system requirement on the download page for Exchange 2007 Sp3 http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=24111 At the same time, I dont see Windows 2008 R2 or Windows 2008 as a supported system on Exchange 2007 Sp1 download page. http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=7170 Good luck !Shaba

Hi Santron Shaba is correct, you cannot install Exchange 2007 RTM on a server running 2008 R2. You will need to get installtion media that already has SP3 included. Cheers, Steve Edit: You may be aware already, but I should add that although installing Exchange on a DC is supported it is not recommended.

I have already installed Exchange 2007 in another domain. It also has only one DC and running same operating system (Windows Server 2008 R2 Service Pack 1 64-bit). But i am not able to install in this. If the installation media has SP3, then the previous system i installed still shows SP1.- Santron Manibharathi.

OK, try this fix then: http://blogs.technet.com/b/exchange/archive/2009/09/15/3408306.aspx

What is the version of Exchange 2007 installation file? RTM, SP1 or SP3? And what error is reported in the setup log?Fiona Liao TechNet Community Support

Installed Exchange Server 2007 SP1 on Windows 2008 R2 Standard SP1. The problem that was previously present is not there when i reinstall both Windows Server and Exchange Server. Some problems arose, it was fixed when disabling ipv6 in registry and while installing mailbox role, the setup is run in compatibility mode of Windows vista SP2. Thanks for the help.- Santron Manibharathi.

I am installing Exchange server 2007 in Windows 2008 R2. The machine i use is the first DC of my domain and the GC. I dont have any other DC. The following error comes when i install. Summary: 4 item(s). 1 succeeded, 3 failed. Elapsed time: 00:00:56 Organization Prerequisites Completed Elapsed Time: 00:00:51 Hub Transport Role Prerequisites Failed Error: Cannot find at least one global catalog server running Windows Server 2003 Service Pack 1 or later in the local Active Directory site. Recommended Action: http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.3&id=67aca4a0-bc3f-4f8f-8297-b13e0d347942 Elapsed Time: 00:00:01 Client Access Role Prerequisites Failed Error: Cannot find at least one global catalog server running Windows Server 2003 Service Pack 1 or later in the local Active Directory site. Recommended Action: http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.3&id=67aca4a0-bc3f-4f8f-8297-b13e0d347942 Elapsed Time: 00:00:01 Mailbox Role Prerequisites Failed Error: Cannot find at least one global catalog server running Windows Server 2003 Service Pack 1 or later in the local Active Directory site. Recommended Action: http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.3&id=67aca4a0-bc3f-4f8f-8297-b13e0d347942 Elapsed Time: 00:00:01 - Santron Manibharathi.