Active Dirctory stürzt ab Event-ID: 16645

Hallo Leute

Windows 2000 Server mit SP4, beim anlegen von Benutzer oder Computern kommt folgende
Meldung:

Event 16645
The maximum account identifier allocated to this domain controller has been assigned. The domain controller has failed to obtain a new identifier pool. A possible reason for this is that the domain controller has been unable to contact the master domain controller. Account creation on this controller will fail until a new pool has been allocated. There may be network or connectivity problems in the domain, or the master domain controller may be offline or missing from the domain. Verify that the master domain controller is running and connected to the domain.

Dabei stürzt ddir Active Dirctory ab und es geht im Netz nichts mehr.
Dringend

Gruss
Bernhard