We have a 32-bit Exchange Server 2003 Standard with SP2 running on a 32-bit Windows Server 2003 R2 Standard with SP2 AD domain. There are no Windows Server 2008 in our network. The mail server is a standalone (AD member). We already have Exchange Server 2007 server license that we purchased a couple of years ago but haven't had time to upgrade yet. Is it straight forward to upgrade our Server 2003 to 2007? We figure we'll have to use a 64-bit OS so introducing a new server (64bit Win 2008) is a must. This is not a problem for us. Is there any other requirements that we overlook? We'd appreciate if someone can point us to an easy to follow upgrade documentation. Thank you.

Sorry, but x86-to-X64 upgrades are not supported. You would have to reinstall from scratch assuming your hardware is 64-bit compliant. But I would want to do that anyway. You can install Server 2008 in a Server 2003 AD, just make sure you're at the latest service pack. It's not a big deal since in-place Exchange upgrades aren't supported either. I hope you're not planning to do this with a single server; you ought to be considering using a swing server or transitioning to new hardware. Also, if you're going to through all of this, you really oiught to consider going to Exchange 2010. It won't be all that long before your Exchange 2007 will be two generations old, meaning that it'll drop off support soon thereafter. Consider running Exchange 2010 SP1 on Windows 2007 R2. Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

Understood. As we mentioned in the original post, we won't be upgrading the current Windows 2003 box. We'll get a new server with 64bit Windows Server 2008, installed as a member of Win2003 AD. Here's the plan: Get a Windows Server 2008. Patch the OS and join 2003 AD domain. Install Exchange Server 2007 and patch it. We don't know how to proceed from there. At some point we'd like to move user mailboxes from 2003 to 2007. Finally, decommission Exchange 2003 box after all mailboxes have been moved to the new server. Not sure the details of installing 2007 with an existing Exchange 2003 machine in the network. We can use some help (documentation). Thanks again.

Got one more question. Our domain and forest functional levels are set to Windows Server 2003 Interim. Will it become a problem if we leave it at that?

In TechNet there are very good documents for the installation and upgrade procedures. All of those things are covered.Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

Hi, >Not sure the details of installing 2007 with an existing Exchange 2003 machine in the network. http://technet.microsoft.com/en-us/library/bb124350(EXCHG.80).aspx >Got one more question. Our domain and forest functional levels are set toWindows Server 2003 Interim. Will it become a problem if we leave it at that? Active Directory must be at Windows Server 2003 forest functionality mode or higher. You have to upgrade it. http://technet.microsoft.com/en-us/library/aa996719.aspxPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.