It should be caused by that the FSMO role owner in question has been unable to contact at least one replication partner to perform replication. Since replication has not occurred the FSMO role holder cannot verify it legitimacy in the environment.
In order for the FSMO role holder to verify it roles replication needs to be restored, the following can be done to restore the FSMO role holders role verification.
Use REPADMIN to determine the failed replication partner/s
If the replication partner/s are offline, bring them online to allow for replication to be resumed
If the replication partner/s are not able to be brought back online then they should be removed using NTDSUtil.
Once all the failed replication partners have been brought online or have been removed from Active directory then the error should be resolved
Microsoft is conducting an online survey to understand your opinion of the Technet Web site. If you choose to participate, the online survey will be presented to you when you leave the Technet Web site.