Not In Windows 2000/2003 Native Mode
Adprep detected that the domain is not in native mode
[Status/Consequence]
Adprep has stopped without making changes.
[User Action]
Configure the domain to run in native mode and re-run domainprep
Raise the domain functional level to 2000 Native mode
To raise Windows 2003 to native mode
1) Open Active Directory Users and computers
2) Right click on your domain name and select Raise Domain Functional Level
3) Use the drop down to select Windows 2000 Native Mode
4) Click Raise