Event 4104, MSDTC Client 2 I am using Idera SQL Diagnostic Manager to monitor a Windows Server Failover Cluster with two SQL Server 2008 R2 clusters configured to run with one SQL Server cluster on each node. It just started reporting that one of the instances does not have DTC or SQL Server Agent installed.

I've RDP'd to the cluster, and both nodes. In the cluster manager I see the DTC node running and is owned by the "A" node. On the "A" node, there are two services called "Distributed Transaction Coordinator." On the "B" node (which is the node on which the instance throwing the error on SQL Diagnostic Manager) there is only one service (in services.msc) called "Distributed Transaction Coordinator."  There is an error in the event log that says: 


  Failed trying to get the state of the cluster node: SERVER-DTC.The
  error code returned: 0x80070005


This cluster node is on the "A" node along with a SQL Server instance. The "B" node has this error. I can list and enumerate jobs in SSMS in the instance that is on the "B" node, but the SQL Server Agent does not have the little green triangle in it (just the empty circle).

So, I don't know exactly what to do. It seems like things are working OK, but this message from Idera SQL Diagnostic Manager has me perplexed since it is new (the error).

Running: 

EXEC master..xp_servicecontrol N'QUERYSTATE', 'MSDTC'


on both nodes results in "Running".
Typically, 0x80070005 is an Access Denied error.  Perhaps the account Idera SQL Diagnostic Manager is using no longer has access to the Service Control Manager on the Windows nodes where the errors are occurring.