Failed to get a connection to a domain controller in domain %1 that User Replicator intended to synchronize. This prevents ...

Failed to get a connection to a domain controller in domain %1 that User Replicator intended to synchronize.  This prevents User Replicator from synchronizing this domain.  This failure occurred because DsGetDcName failed to give a valid domain controller to connect to.  DsGetDcName failures usually stop occurring after some time.  If this error continues to occur, the computer should be rebooted to fix the NetLogon service which calls DsGetDcName.