I am sure you guys have seen the following error message before when you try to install DPM on a Windows 2008 server.
"Microsoft System Center Data Protection Manager 2007 is not supported on this operating system"
A lot of people recently asked me about this error message. You will get this error message if you are trying to install DPM on a Domain Controller. I know the error message is confusing but DPM 2007 is fully supported on a Windows 2008 server. As recommended, do not install applications on Domain Controllers.