Windows Server 2003 R2 AD not compatible

I had to migrate a Windows 2003 SBS (32 bit) to Windows 2003 R2 standard (64 bit).
At the moment that I had to add a second Domain Controller to the company’s domain it went wrong.

I couldn’t do the ‘dcpromo’ because The Active Directory was not compatible.

You need to do the adprep command of a R2 edition, in my case Windows Server 2003 R2 32 bit, not of the original cd’s with SBS 32 bit.

To apply Windows Server 2003 R2 schema extensions to the Active Directory schema do the following:

  • Insert the second Windows Server 2003 R2 installation disc in the CD drive of the server that holds the schema master operations role (also known as flexible single master operations (FSMO)).
  • Log on to the computer as a member of the Schema Admins group.
  • Go to Start > Run > cmd <enter>, you will get the Command Prompt.
  • At the command prompt, type the following commands, substituting the drive letter of the CD drive for driveexample:
cd tsclientEcmpnentsR2adprep
adprep /forestprep
adprep /domainprep