Error while raising domain function from Windows 2000 to Windows 2003

I am getting error while raising certain domain functions. I am trying to do that from Windows 2000 to Window \s 2003. The error that I am getting below is about missing object value. It looks the server is not processing any require here. I am using that thorugh dcdaig /v /c /e. The error listed was CN=LostAndFoundConfig,CN=Configuration,DC=hymall,DC=corp - relate to some DC Account Object.

This cannot be done; the raising of the domain functional level is a one-way process. You would necessitate reinstalling AD to perform so. This means that you necessitate demoting all of your DCs, after that re-Dcpromo them with the new domain name and FL.