Attempting to mount Exchange Server 2016 DAG database with 1 of 2 nodes down throws the error: “Error: An Active Manager operation failed. Error: An Active Manager operation encountered an error. To perform this operation, the server must be a member of a database availability group, and the database availability group must have quorum. Error: Automount consensus not reached (Reason: ConcensusUnanimity does not allow auto mount. (IsAllNodesUp: False)).”

Problem

You have two Exchange 2016 mailbox servers configured as a DAG and one server providing witness servers.  One of the mailbox server experiences an issue and goes down so the remaining mailbox server continues to service mailbox requests and has the databases mounted.  The remaining operational server is restarted and you immediately notice that the databases are not mounted after the restart: 

Attempting to mount the databases with the Mount-Database command throws the following error:

[PS] C:\Windows\system32>Mount-Database contoso-edb16-01

Failed to mount database "contoso-edb16-01". Error: An Active Manager operation failed. Error: An Active Manager operation

encountered an error. To perform this operation, the server must be a member of a database availability group, and the

database availability group must have quorum. Error: Automount consensus not reached (Reason: ConcensusUnanimity does

not allow auto mount. (IsAllNodesUp: False)). [Server: contoso-MBX16-01.contoso.NET]

    + CategoryInfo          : InvalidOperation: (contoso-EDB16-01:ADObjectId) [Mount-Database], InvalidOperationException

    + FullyQualifiedErrorId : [Server=contoso-MBX16-01,RequestId=ae45aaee-8113-4908-a0fd-34e3d4a032a2,TimeStamp=17/08/2017

    12:20:16] [FailureCategory=Cmdlet-InvalidOperationException] A5CACA44,Microsoft.Exchange.Management.SystemConfigu

  rationTasks.MountDatabase

    + PSComputerName        : contoso-mbx16-01.contoso.net

[PS] C:\Windows\system32>Get-DatabaseAvailabilityGroup

Executing the Get-DatabaseAvailabilityGroup cmdlet displays the following message:

Warning: Unable to get Primary Active Manager information due to an Active Manager call failure. Error: An Active Manager operation failed. Error: An Active Manager operation encountered and error. To perform this operation, the server must be a member of a database availability group, and the database availability group must have a quorum. Error: Automount consensus not reached (Reason: ConcensusUnanimity does not allow auto mount. (IsAllNodesUp: False)).

Executing the Get-MailboxDatabaseCopyStatus * cmdlet indicates the status of the mailbox databases in the DAG as Unknown:

Solution

The reason why the databases would not automount and manually mounting them would fail is because the DAG has Datacenter Activation Coordination (DAC) mode enabled and this forces starting DAG members to acquire permission in order to mount any mailbox databases.  In the example above, the DAG is unable to achieve a quorum with the second node down and therefore the DAG isn’t started and databases would not be able to mount.  If you are sure that the second node is down as in the example above, you can manually start the DAG with the cmdlet:

Start-DatabaseAvailabilityGroup -Identity <DAG NAME> -MailboxServer <MailboxServerName>

The status of the mailbox databases should now be listed from Unknown to Dismounted once the DAG has been started and issuing the Mount-Database cmdlet will now successfully mount the databases:

The following are TechNet blog posts that provide a more in depth explanation of DAG and DAC:

Part 1: My databases do not automatically mount after I enabled Datacenter Activation Coordination
https://blogs.technet.microsoft.com/timmcmic/2012/05/21/part-1-my-databases-do-not-automatically-mount-after-i-enabled-datacenter-activation-coordination/

Part 5: Datacenter Activation Coordination: How do I force automount consensus?
https://blogs.technet.microsoft.com/timmcmic/2013/01/27/part-5-datacenter-activation-coordination-how-do-i-force-automount-consensus/

Attempting to export an Exchange Server mailbox to PST throws the error: “Couldn’t locate a database suitable for storing this request.”

I’ve noticed that many of my colleagues and clients have asked me about the following error that is thrown when they attempt to export an Exchange Server mailbox to PST so I thought it would be a good idea to quickly write a post about the error.

Problem

You attempt to export a mailbox to PST via the Exchange Admin Center but received the following error:

Couldn’t locate a database suitable for storing this request.

Using the New-MailboxExportRequest feature displays a similar error:

[PS] C:\Windows\system32>New-MailboxExportRequest -Mailbox mbraithwaite -FilePath "\\tmrfp09\archive$\Outlook Archive\mb
raithwaite.pst"
Couldn't locate a database suitable for storing this request.
     + CategoryInfo          : InvalidArgument: (mbraithwaite:MailboxOrMailUserIdParameter) [New-MailboxExportRequest],
     MailboxDatabase...manentException
     + FullyQualifiedErrorId : [Server=contBMEXMB01,RequestId=c7446094-7d17-4e06-90c4-07be8ca10829,TimeStamp=8/23/2017 2
    :46:00 PM] [FailureCategory=Cmdlet-MailboxDatabaseVersionUnsupportedPermanentException] 4B192EAA,Microsoft.Exchang
   e.Management.Migration.MailboxReplication.MailboxExportRequest.NewMailboxExportRequest
     + PSComputerName        : contbmexmb01.contoso.com

[PS] C:\Windows\system32>

Solution

The reason why this error would be thrown is if you are trying to export a mailbox that is on a different version than the admin console you are working from.  In the example above, the attempt was made from the Exchange 2016 admin center but the mailbox actually resides on an Exchange 2010 server.  Simply execute the export job from the PowerShell prompt of one of the Exchange 2010 servers to get the mailbox to export.

Exchange 2010 users are no longer able to connect via Outlook Anywhere while migrating to Exchange 2016

I’ve recently had to migrate a client from Exchange 2010 to 2016 and quickly noticed that Outlook Anywhere no longer worked after redirecting Outlook Anywhere and other services such as autodiscover and webmail to the new server.  Outlook Anywhere continued to work for users migrated to Exchange 2016 but not for users still on the legacy Exchange server.  Using the Remote Connectivity Analyzer (https://testconnectivity.microsoft.com/) Outlook Connectivity feature would fail and throw the following error:

Attempting to send an Autodiscover POST request to potential Autodiscover URLs.

Autodiscover settings weren't obtained when the Autodiscover POST request was sent.

Additional Details Elapsed Time: 1504 ms.

Test Steps The Microsoft Connectivity Analyzer is attempting to retrieve an XML Autodiscover response from URL https://autodiscover.domain.com:443/Autodiscover/Autodiscover.xml for user user@domain.com. The Microsoft Connectivity Analyzer failed to obtain an Autodiscover XML response. Additional Details A Web exception occurred because an HTTP 400 - BadRequest response was received from Unknown. HTTP Response Headers: request-id: 0d7c484b-cdfb-42eb-bd3b-8d5b6dfb4844 X-CalculatedBETarget: exchange2010-02.domain.com Persistent-Auth: true X-FEServer: exchange-2016-02 Strict-Transport-Security: max-age=157680000 Content-Length: 346 Cache-Control: private Content-Type: text/html; charset=us-ascii Date: Wed, 16 Aug 2017 17:06:18 GMT Set-Cookie: X-BackEndCookie=S-1-5-21-206374890-975330658-925700815-6573=rJqNiZqNgauyrbqnt7zPzdGLkJSWkJKWk5OakZGWipLRnJCSgc7GzMjGxsjGy8iBzc/OyNLPx9LOyavOyMXOycXOxw==; expires=Wed, 16-Aug-2017 17:16:18 GMT; path=/Autodiscover; secure; HttpOnly Server: Microsoft-IIS/8.5 X-AspNet-Version: 4.0.30319 X-Powered-By: ASP.NET Elapsed Time: 1504 ms.

I was unable to find an official Microsoft KB which described this issue but I was able to come across this blog post for migrating from Exchange 2007 to Exchange 2013:

Exchange 2013 to 2007 Outlook Anywhere Proxy Issue
https://smtp4it.net/2013/12/05/exchange-2013-to-2007-outlook-anywhere-proxy-issue/

… and I can confirm that after adding the registry keys onto the Exchange 2010 servers as such:

… then restarting the servers was able to correct the Outlook Anywhere problem for Exchange 2010 users during the Exchange 2016 migration:

Attempting to launch a Citrix XenApp / XenDesktop 7.x application published with a NetScaler VPX fails with: “Unable to launch your application. Contact your help desk with the following information: Cannot connect to the Citrix XenApp server. Network issues are preventing your connection. Please try again. If the problem persists, please call your help desk.”

Problem

You attempt to launch a Citrix XenApp / XenDesktop 7.x application published with a NetScaler VPX:

The following Citrix Receiver Remote Desktop Connection window is presented and displays the progress bar:

Starting…

More information

Clicking on the More information button displays:

Connection in progress…

Less information

The progress bar does not proceed any further and the process eventually fails with the message:

Unable to launch your application. Contact your help desk with the following information:

Cannot connect to the Citrix XenApp server. Network issues are preventing your connection. Please try again. If the problem persists, please call your help desk.

Attempting to launch the XenApp desktop displays the launch window:

… but will fail with:

The connection to “XenApp Weir Desktop” failed with status (Unknown client error 1110).

Solution

While there could be several reasons why this error would be thrown, one of the possible causes is if the Citrix session reliability port 2598 is blocked from NetScaler to application server.  Ensure that the NetScaler can access the XenApp server via TCP port 2598.