This article describes how to troubleshoot the DFS Replication Service 4012 error.
In the Windows event log you have an error like this:
The DFS Replication service stopped replication on the folder to the following local path: C: \ Windows \ SYSVOL \ domain. This server was disconnected from the other partners for a period of 690 days, which is a longer period than allowed by the MaxOfflineTimelnDays (60) parameter. DFS Replication considers the data in this folder as stale. This server will not replicate folder until this error is corrected.
This error occurs mainly on domain controllers that do not have to replicate.
Resolution
1. On each server, open a command prompt in Administrator and enter the following command to change the value of MaxOfflineTimeInDays. The new value must be greater than the non-synchronization period.
wmic.exe /namespace:\\root\microsoftdfs path DfsrMachineConfig set MaxOfflineTimeInDays=7002. On each server restart the DFS Replication service.
3. Verify that error 4012 is not displayed in the most event log. It is also possible to test replication by copying a file to a server’s NETLOGON folder and verifying that the server replicates.
The problem completely solved, think about setting the MaxOfflineTimeInDays value to 60.