Microsoft Windows has been known for the fact that it isn’t very vulnerable for dirty shutdowns for example by a power outage. Of course an unexpected shutdown during a windows update installation could be harmful but since Windows 7/Server 2008 R2 even that has become less of an risk.
However there’s one part of Windows that stops after a dirty shutdown and that is DFS-R which is especially painfull when it is used for Active Directory replication. The fact that this behavior is as designed but not well communicated by Microsoft can cause domain controllers become out of sync with different versions of group policies as a result.
In the event viewer the following event will be written:
The wmic command mention in the event description will re-enable DFS-R but won’t prevent DFS-R to stop again after a reoccurring dirty shutdown. To make sure DFS-R keeps working after a dirty shutdown the following registry key can be configured on the servers:
After this key has been created and the server has been restarted, DFS-R will resume after a dirty shutdown. This key also can be rolled out using a group policy computer preference on all DFS-R enabled servers (Domain controller,file servers etc)
Be warned that auto-recovery can lead to unwanted rollbacks of DFS-R data in some circumstances so always makes sure you backup your servers regularly!