I am looking to upgrade the domain controllers in our lab to Windows Server 2008 R2 from Server 2003. Are there any issues in relation to the domain and forest function levels if I do not have the resoucres to upgrade the Exchange 2003 that is installed on a member server? Any help would be appreciated as I haven't seen anything out on the net in regards to this.

The latest support info relates only to Windows 2008 DCs. No mention of 2008 R2 DCs and Exchange 2003.http://msexchangeteam.com/archive/2007/08/16/446709.aspxI suspect you wont find much since Exch 2003 is out of mainstream support. But since its a lab...

Hi,In addition to Andy, please understand that the Exchange 2007 start to support for Windows Server 2008 R2 Domain Controllers in the environment since Service Pack 1 Rollup 9. For your reference: Update Rollup 9 for Exchange Server 2007 Service Pack 1 has been released http://msexchangeteam.com/archive/2009/07/17/451835.aspx As Exchange 2003 is out of mainstream support, I do not find any official document regarding Exchange 2003 and Server 2008 R2 Doman Controller, we cannot guarantee that Exchange 2003 will work correctly in a Windows 2008 R2 functional level domain. Other information: Exchange 2007 SP2 Setup fails if all domain controllers are running Windows Server 2008 R2 http://msexchangeteam.com/archive/2009/09/02/452284.aspx Mike Shen TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com

Hi, After some further research, I think the Windows Server 2008 R2 AD is not supported for Exchange 2003. For your reference: Exchange Server Supportability Matrixhttp://technet.microsoft.com/en-us/library/ee338574.aspxThanks,Mike

Thanks for the link. It was precisely what I was looking for and prevented me from going down the wrong path. That also answered the same questions we will have with an Exchange 2007 lab as well. Brian

According to this matrix Exchange 2003 SP2 is supported with 2008 R2 DC's including the functional level of both the forest and domain, so I don't understand why you sent this link saying that it's NOT supported? Please clarify...thank you!