It look slike our DAG computer account has been deleted. Its been awhile so I don't think I will be able to restore it. Can I simply remove the servers from the current DAG create a new one, then move them in there?

what you mean by DAG computer name? you mean you have removed the DAG?

When you create a DAG it create a computer account in active directory. That computer account is no longer there. I think it's actually the cluster name. 

This looks like the exact problem but I can't restore the account.

https://social.technet.microsoft.com/Forums/en-US/adb82086-c0bd-4c43-b41c-2f0d7c1aeb67/exchange-2010-dag-deleted-dag?forum=exchange2010

Or should I follow these steps? From https://social.technet.microsoft.com/Forums/en-US/adb82086-c0bd-4c43-b41c-2f0d7c1aeb67/exchange-2010-dag-deleted-dag?forum=exchange2010

You can create create new CNO and replace the deleted CNO for DAG.

• Create a new computer account for the CNO named the same as the DAG.
• Give the DAG nodes (computer accounts) full control permission to the CNO.
• Identify the objectGUID attribute for the CNO and make note of it. This will be added to the cluster configuration.
• On one of the DAG nodes, use Regedit and view HKLM\Cluster and identify the value ofClusterNameResource. It will be a long ugly number and is the Cluster Name Resource GUID.
• In Regedit on Mailbox server, browse toHKLM\Cluster\Resources\ClusterNameResourceGUID\Parameters.
• Edit the ObjectGUID key and replace the value with the value you copied in step 3. This tells the cluster to use the new CNO.
• Perform steps 5 and 6 on all DAG nodes.
• Restart the Cluster service on all DAG nodes.

Hi,

Yes. In your case, the DAG computer account has been removed, you can create a new computer account for the CNO to replace the deleted CNO for your DAG.

For more information, here are some helpful threads for your reference.

https://technet.microsoft.com/en-gb/library/ff367878(v=exchg.141).aspx

http://blogs.technet.com/b/askcore/archive/2009/04/27/recovering-a-deleted-cluster-name-object-cno-in-a-windows-server-2008-failover-cluster.aspx

Hope this can be helpful to you.

Best regards,

Hi,

Any update?

Best regards,

I'm sorry I never got the notice to your response. I will give recreating the dag account and updating the GUID's on the two DAG members hopefully this weekend. I'm a little nervous to restart the cluster service as things are running now so waiting till off hours seems prudent. I will update as soon as I get some results. Thanks!

it was nice articles, i understand this is not a straight forward simple fix, we must undergo lot of things to resolve this issue. thanks for your response.

Hi,

I am just writing to see if you have obtained the opportunity to test the solution. If anything is unclear with the previous information I have provided, please let me know.

Best regards,