64-bit Exchange a Possibility for Post-2003 Version

Will Exchange Server 2003 support Windows Server 2003? Seems like a simple question, but with Microsoft's myriad server OS editions, the answer gets complicated.

In almost all real-world usage scenarios, the answer is yes. But the introduction in the Windows Server 2003 generation of two 64-bit editions and a Web Edition make the answer less black and white.

Exchange Server 2003's primary purpose appears to be to bring Microsoft's flagship messaging platform up to speed with Windows Server 2003, which shipped April 24. While it will run on Windows 2000 Server with Service Pack 3, many of its best new features consist of support for Windows Server 2003 technology enhancements.

They include eight-node failover clustering, Volume Shadow Copy services and the locked-down security settings. In fact, Microsoft won't support Exchange 2000 on Windows Server 2003. Company officials say the reason is that it would be too much work to make Exchange 2000 comply with all of Windows Server 2003's new security requirements.

Of Windows Server 2003's six editions, Exchange Server 2003 will support three -- Windows Server 2003 Standard Edition, Windows Server 2003 Enterprise Edition and Windows Server 2003 Datacenter Edition.

Exchange Server 2003 won't support the less expensive new Web Edition, which a spokesman says is due to the Web Edition's incomplete support for Active Directory, a central requirement of Exchange Server 2003.

And Exchange Server 2003 doesn't support the new 64-bit versions of Windows Server 2003 Enterprise Edition and Windows Server 2003 Datacenter Edition. This isn't surprising, given the database-centric focus of the 64-bit edition and the lack of a current demand for throwing dozens of gigabytes of memory at e-mail servers.

"[Sixty-four-bit support] is something that we are evaluating right now. It's something we would basically be looking at for the next version of Exchange," said Missy Stern, a Microsoft product manager for Exchange.

Looking in the other direction from the server OS, Exchange Server 2003 will support three versions of the Outlook client -- Outlook 2000, Outlook 2002 and the soon-to-ship Outlook 2003.

About the Author

Scott Bekker is editor in chief of Redmond Channel Partner magazine.