This problem generally occurs only if the domain controller that you restore is the only domain controller in the domain, or if all of the domain controllers in the domain have also been restored (for example, to duplicate a production environment in a lab).
This behavior occurs because the File Replication service (FRS) cannot locate a valid replication partner to synchronize the Sysvol replica set.
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows
You must designate one domain controller as being authoritative for the Sysvol replica set. If all of the domain controllers in the domain have been restored, select the primary domain controller emulator flexible single master operations (FSMO) role holder:
Stop the File Replication service on the domain controller.
Start Registry Editor (Regedt32.exe).
Locate and then click the BurFlags value under the following key in the registry:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NtFrs\Parameters\Backup/Restore\Process at Startup
On the Edit menu, click DWORD, click Hex, type D4, and then click OK.
Quit Registry Editor.
Move data out of the PreExisting folder.
Restart the File Replication Service.
Note This registry value marks the FRS replica as authoritative for the whole replica set. Set this value on only one replica, and only to resolve this specific issue. If you configure multiple replicas as authoritative, conflicts and collisions may occur in the replica set.
When you set the D4 registry setting on one domain controller, you must set the D2 registry setting on every other domain controller. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
315457 How to Rebuild SYSVOL and Its Content in a Domain
This behavior is by design.
When you restore a domain controller from backup (or when you restore the System State), the FRS database is not restored because the most up-to-date state exists on a current replica instead of in the restored database. When FRS starts, it enters a "seeding" state and then tries to locate a replica with which it can synchronize. Until FRS completes replication, it cannot share Sysvol and Netlogon.
If you restore all of the domain controllers in the domain backup, all the domain controllers enter the seeding state for FRS and try to synchronize with an online replica. This replication does not occur because all of the domain controllers are in the same seeding state. Setting the primary domain controller FSMO role holder to be authoritative forces the domain controller to rebuild its database based on the current contents of the system volume. When that task is completed, the Sysvol and Netlogon shares are shared. All the other domain controllers can then start synchronizing from the online replica.