Windows 2003 Domain Rename and Exchange error

I have been working with a company that wants to rename their forest root domain (for political reasons). We have gone through the planning, made sure that everything meets the prerequisites. Forest and domains are in Windows 2003 functional level, E2K3 server is E2K3 SP2, I have the necessary rights, all the DC's are healthy and available on the network, yet when I ran the rendom.exe /upload I got this message:

C:\DomainRename>rendom /upload
Found Exchange Server(s) in the forest.Domain rename is supported only if Exchange server version is Exchange 2003 SP1 and above.
: The server is unwilling to process the request. :8245

I posted questions on newsgroups and used up some techie karma asking everyone I knew that might know the solution. I searched high, I searched low and everything pointed to the forest or a domain not being in Windows 2003 functional level. The problem was, in all my searches, I was including the code 8245 in the search.

Finally, today I called PSS. The second technician I talked to said, have you seen KB 891370: "You receive an error message when Rendom.exe changes the DNS or NetBIOS name of a domain in Windows Server 2003"

The problem is there were a couple of Exchange system policies that did not have a versionNumber attribute. Once I corrected this, rendom.exe /upload ran fine. Hopefully this has corrected the problem. It is just embarassing that I did not come across this on my own. Too bad the KB article does not include the whole error.

If you are planning a domain rename, read the documentation thoroughly and get the latest version from Microsoft's web site. Renaming a domain is not a trivial operation.