Authoritative restore Windows 2008 DC

I want to restore a deleted object from AD. All domain controllers are Windows 2008 and I have restarted the DC and the object got deleted on into DSRM, we user NetBackup for restoring the system state to the DC. I went into ntdsutil and ran "ac i ntds". This command completed without any errors. After that I ran "au r" and it gave me error saying that "Could not initialize the jet engine: jet error -542 could not check if the domain controller is read-only". What kind of error is this and how to fix it? Thanks.

You can try to Perform Authoritative Restore of Active Directory Objects by following the link here - http://technet.microsoft.com/en-us/l.../cc816878.aspx