ADPREP WARNING: Before running adprep, all Windows 2000 Active Directory Domain Controllers in the forest should be upgraded ...

ADPREP WARNING: 

Before running adprep, all Windows 2000 Active Directory Domain Controllers in the forest should be upgraded to Windows 2000 Service Pack 4 (SP4) or later. 

[User Action] 
If ALL your existing Windows 2000 Active Directory Domain Controllers meet this requirement, type C and then press ENTER to continue. Otherwise, type any other key and press ENTER to quit.