PowerEdge: DFSR Error 4004 code 9003 on Windows server

• Distributed File System replication (DFSR) is failing.
• The DFS Replication event log shows error 4004, with error code 9003, "The replication group is invalid," in the description. There are other possible error codes for this event. This article may not be applicable to anything but error code 9003.

The issue can be resolved by deleting the DFSR database and allowing the system to rebuild it. To do this, perform the following steps on the affected server:

1. Stop the DFS Replication service.
2. Locate the DFSR database, which should be in the X:\System Volume Information\DFSR\database_<string> folder. (Replace X: With the letter of the volume where the DFSR content is stored.)
   • By default, only the SYSTEM account has access to the System Volume Information folder. It is necessary to modify the permissions on this folder in order to gain access, and it may also be necessary to take ownership of the folder.
3. Copy the folder to a safe location, in case something goes wrong.
4. Delete everything in the folder. It is not necessary to delete the folder itself.
   • Even with Full Control permissions on this folder, you may receive an "Access denied" error when attempting to delete its contents. If this occurs, you can likely delete the files from an elevated command prompt.
5. Start the DFS Replication service. A new database is automatically created, and this should resolve the issue.