I have seen conflicting information about Exchange 2003 and Active Directory 2008 R2. We have an old Windows 2003 R2 domain with a new dedicated server running nothing but Exchange 2003 SP2 Standard on Windows Server 2003 R2. We need to keep Exchange 2003 running until we can retire some Outlook 2000 clients. We have one domain, one Routing Group, one Server, one Information Store. Can Exchange 2003 SP2 run if we retire the old Domain Controllers and run Windows 2008 R2 Domain Controllers?

Hi, If you want the Microsoft definitive answer, Exchange Server 2003 SP2 is NOT supported in a Windows Server 2008 R2 Active Directory. http://technet.microsoft.com/en-us/library/ee338574.aspx yields the matrix (look under Supported Active Directory Environments) I hope this will help you. Regards. Shafaquat Ali.M.C.I.T.P Exchange 2007/2010, M.C.I.T.P Windows Server 2008, M.C.T.S OCS Server 2007 R2, Phone: +923008210320

As in more details It states quite clearly that read only 2008/2008R2 domain controllers are not supported; standard (i.e. writable) DCs are supported. It also states that 2008/2008R2 domain and forest functional levels are supported. What is not supported is running Exchange 2003 on a 2008/2008R2 server. Regards. Shafaquat Ali. M.C.I.T.P Exchange 2007/2010, M.C.I.T.P Windows Server 2008, M.C.T.S OCS Server 2007 R2, Phone: +923008210320

One would expect that the developers of Active Directory 2008 and R2 were careful not to break Exchange 2003, but I found a lot of information to the contrary, and the official support matrix is hard to find. Thanks for pointing me to it. We have no need for Read Only Domain Controllers and are pleased to learn that we can run Exchange 2003 SP2 on Windows 2003 R2 in an AD 2008 R2 domain. Thanks.