First of all, I understand that Exchange 2007 SP3 is the only supported Exchange 2007 version on Windows 2008 R2 OS. Now that I have that out of the way, we had a guy who managed to cram Exchange 2007 w/ SP1 and even update rollup 10 for it onto Windows 2008 R2. Personally, this install failed for me, but I'm way beyond that. I need to get at least Exchange 2007 SP2 on it and if I can't, can anyone tell me if Exchange 2007 SP3 would allow the install to start? thanks.

Depends, the upgrade scenario is not supported in the following. Also is it possible to get a non supported version of Exchange on a non supported OS in general? Yes people have done it before including myself by changing the compataiblity mode of the .exe. However this is discouraged because in my test lab when you have unsupported scenarios you will run into issues down the line such as not being able to add\remove roles anymore and such. Windows Server 2008 R2 and Windows 7 Installations Exchange 2007 SP3 is supported on Windows Server 2008 R2. The Exchange Server 2007 SP3 Management Tools are supported on Windows 7. However, Exchange 2007 SP3 provides support only for a new installation of Exchange that is running on these operating systems. Exchange 2007 SP3 is not supported in an upgrade scenario on Windows Server 2008 R2 or on Windows 7. For example, Exchange 2007 SP3 does not support the following installation scenarios: Performing a new installation of Exchange 2007 SP3 on a Windows Server 2008 R2-based computer or on a Windows 7-based computer that is upgraded from Windows Server 2008 or from Windows Vista Upgrading Exchange 2007 SP2 to Exchange 2007 SP3 on a Windows Server 2008 R2-based computer or on a Windows 7-based computer that is upgraded from Windows Server 2008 or from Windows Vista Upgrading the operating system from Windows Server 2008 or from Windows Vista to Windows Server 2008 R2 or to Windows 7 if Exchange 2007 SP3 is installed Performing a slipstream upgrade of Exchange 2007 SP3 on a Windows Server 2003-based computer, on a Windows Server 2008 -based computer, or on a Windows Vista-based computer. SP3 on R2 scenarios other than stated below are Not supported: http://technet.microsoft.com/en-us/library/ff607233(EXCHG.80).aspx James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

Yep, I'm aware of this as I stated. I've even got a response from a Microsoft guy here online. I've read the section of sentences in the past already. I don't have a test server and I don't have a test environment either. I need to know if I can do this even if it involves a roundabout way of doing it. I have no choice but to get this installed somehow.

You want to get sp2 or sp3 installed? Right click the setup.exe, compabiltity tab, change the OS. Can't gurantee it will work since "things" evolve from when I did it a long time back. James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

Hi, That is not supported. You have to own the risk. Any unexpected issue would not be supported by microsoft. Xiu Zhang TechNet Community Support