Users planning to run Microsoft Exchange on Windows Server 2008 and those contemplating in-place upgrades of the new server operating system coming out this week may face installation problems unless they heed specific advice from Microsoft.
The vendor is already warning users that the RTM version of Exchange 2007 cannot be installed on Windows Server 2008 and that it is impossible to do an in-place upgrade to Windows Server 2008 on a server running Exchange 2007 SP1.
Microsoft also has said that "rolling upgrades" of failover clusters for Exchange are impossible.
Microsoft has published three migration options, including one long set of steps around off-loading data, uninstalling and reinstalling numerous Exchange components.
The other upgrade issue centres on a confusing dialog box that partners say could freeze administrators doing in-place upgrades and points to the fact that in-place Windows Server 2008 upgrades for application servers could be a crap-shoot, if not impossible, much like Exchange.
The dialog box carries the message: "If you are using 3rd-party apps you are not supported". It will pop up during in-place upgrades from Windows Server 2003 to 2008 on servers running applications.
Microsoft acknowledges the existence of the dialog box, which was added during the Release Candidate beta cycle of Window Server 2008.
Microsoft partners say the vendor told them it made changes in the in-place upgrade procedures for Windows Server 2008, but Microsoft has not detailed those changes to partners.
The only supported option for in-place upgrades is when replacing servers that run core infrastructure services such as DNS, DHCP or Active Directory, according to Microsoft.
In other cases, Microsoft recommends that before installing Windows Server 2008 users uninstall third-party applications or applications that did not ship with Windows Server 2003 or that were not delivered via Windows Update. Once the server is installed, the applications and any corresponding data can be reinstalled, a similar procedure suggested with Exchange.