Password hash synchronization failed for domain: welaye.com, domain controller hostname: zentyal.welaye.com, domain controller IP address: 10.0.1.1. Details: 
Microsoft.Online.PasswordSynchronization.SynchronizationManagerException: Recovery task failed. ---> Microsoft.Online.PasswordSynchronization.DirectoryReplicationServices.DrsException: RPC Error 8420 : The naming context could not be found. There was an error calling _IDL_DRSGetNCChanges.
   at Microsoft.Online.PasswordSynchronization.DirectoryReplicationServices.DrsRpcConnection.OnReplicateSingleObject(DsName directoryName)
   at Microsoft.Online.PasswordSynchronization.DirectoryReplicationServices.DrsConnection.ReplicateSingleObject(Guid objectGuid, String distinguishedName)
   at Microsoft.Online.PasswordSynchronization.RecoveryTask.<>c__DisplayClass9_0.<RetrieveObjectChangesFromAD>b__1(IDrsConnection c)
   at Microsoft.Online.PasswordSynchronization.RetryUtility.ExecuteWithRetry[T](Func`1 operation, Func`1 shouldAbort, RetryPolicyHandler retryPolicy)
   at Microsoft.Online.PasswordSynchronization.RecoveryTask.RetrieveObjectChangesFromAD(List`1 retryObjects)
   at Microsoft.Online.PasswordSynchronization.RecoveryTask.SynchronizeCredentialsToCloud()
   --- End of inner exception stack trace ---
   at Microsoft.Online.PasswordSynchronization.RecoveryTask.SynchronizeCredentialsToCloud()
   at Microsoft.Online.PasswordSynchronization.PasswordSynchronizationTask.SynchronizeSecrets()
   at Microsoft.Online.PasswordSynchronization.SynchronizationExecutionContext.SynchronizeDomain()
   at Microsoft.Online.PasswordSynchronization.SynchronizationManager.SynchronizeDomain(SynchronizationExecutionContext syncExecutionContext)
Microsoft.Online.PasswordSynchronization.SynchronizationManagerException: Recovery task failed. ---> Microsoft.Online.PasswordSynchronization.DirectoryReplicationServices.DrsException: RPC Error 8420 : The naming context could not be found. There was an error calling _IDL_DRSGetNCChanges.
   at Microsoft.Online.PasswordSynchronization.DirectoryReplicationServices.DrsRpcConnection.OnReplicateSingleObject(DsName directoryName)
   at Microsoft.Online.PasswordSynchronization.DirectoryReplicationServices.DrsConnection.ReplicateSingleObject(Guid objectGuid, String distinguishedName)
   at Microsoft.Online.PasswordSynchronization.RecoveryTask.<>c__DisplayClass9_0.<RetrieveObjectChangesFromAD>b__1(IDrsConnection c)
   at Microsoft.Online.PasswordSynchronization.RetryUtility.ExecuteWithRetry[T](Func`1 operation, Func`1 shouldAbort, RetryPolicyHandler retryPolicy)
   at Microsoft.Online.PasswordSynchronization.RecoveryTask.RetrieveObjectChangesFromAD(List`1 retryObjects)
   at Microsoft.Online.PasswordSynchronization.RecoveryTask.SynchronizeCredentialsToCloud()
   --- End of inner exception stack trace ---
   at Microsoft.Online.PasswordSynchronization.RecoveryTask.SynchronizeCredentialsToCloud()
   at Microsoft.Online.PasswordSynchronization.PasswordSynchronizationTask.SynchronizeSecrets()
   at Microsoft.Online.PasswordSynchronization.SynchronizationExecutionContext.SynchronizeDomain()
   at Microsoft.Online.PasswordSynchronization.SynchronizationManager.SynchronizeDomain(SynchronizationExecutionContext syncExecutionContext)
.

<forest-info>
  <forest-name>WELAYE.COM</forest-name>
  <connector-id>ec42ec54-b10d-4a11-8e4c-c0ebf9c47436</connector-id>
</forest-info>