Dear:

These things could casue this error as follow:

1- Old version of O/S still on the device.
2- Old Active directory files.
3- Another database file like(Novel,etc..).

these all the causes that influnce on this..

Best regard

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You should at least of two domain controllers in your active directory environment. If you have two and one starts to act up.
1. de-promo the domain controller
2. Remove it from the domain.
3. Clean up the metadata in AD
4. Re-install the operating system
5. add it to the domain
6. Promote it to a domain controller

If that server is your only domain controller, you need to add a temporary domain controller then do the steps above. This <a href=”http://technet.microsoft.com/en-us/library/cc736378.aspx”>link</a> will step you through cleaning up the metadata.