How to remove a dead Exchange Server from Active Directory?

Just like any software, your Exchange Server can also get beyond repair and recovery for a host of reasons. In such a case, it is best you remove that dead exchange server from active directory.

That said, removing a dead exchange server is anything but easy because it is intertwined with many applications in your system. You will have to ensure that all connectors, mailbox databases and public folder databases associated with the dead server is removed before you can de-install it.

Before moving into the exact removal procedure, here are some aspects to keep in mind.

• The most ideal way is to use add/remove programs to uninstall Exchange server.
• The Exchange server should be beyond recover, if you want to completely remove it from your organization.
• If you plan to recover your server at some point in time, these steps are not meant for you.
• You have to remove the configurations and connectors separately.
• More work is required to completely clean all trace of the server.

All this could entail a considerable amount of time and resources, so make sure you know what you're getting into. If you still decide to go ahead with it, here are some ways to remove a dead Exchange server from Active Directory.

Using Exchange Management Shell

One way to remove a dead exchange server is to use the Exchange Management Shell , a command prompt tool that is pre-loaded with PowerShell commands. You can also an Exchange Management Console (EMC), if that works better for you.

As a first step, replicate the public folders. Simply copy the contents of these folders to a different location, so you can replicate them back to the new server. But sometimes, even after you do this, the dead server will give you an error message saying that you have to remove the public folders before de-installing them. One way to overcome this problem is to use the script called "MoveAllReplicas" that takes two parameters, namely, the source and target server. The syntax is

MoveAllReplicas - sourceserver [server] -targetsever [server]

This step can take a few minutes to execute, so be ready for it.

Once this is done, you'll have to remove the legacy connectors. To do this, run the cmdlet called "remove-routinggroupconnector [GUID]", where GUID is the group ID of connectors. You will face this legacy connector problem in all versions from 2003 to 2010.

Using ADSIEdit

If you have Microsoft Exchange 2013, a good option is to use ADSIEdit tool.  

Below are the steps to use this tool.

• Go to Windows Run, type ADSIEdit.msc and click "Run"
• Right-click on ADSIEdit and choose the "Connect to.." option.
• This will open a new dialog box. In that dialog box, give the name as "Configuration" and click OK
• On the left hand pane, expand Configuration > CN = Configuration > CN=Services > CN = Microsoft Exchange > CN = <organization name> > CN=Administrative groups > CN=Exchange Server Administrative Groups > CN=Servers. This will display all the servers on the right hand pane. Choose the one that you want to remove.
• When you know for sure that you do not want that server in your system anymore, right-click on it and choose the "delete" option. This should remove the server for you.

However, that is not the end as you'll have to manually remove any connectors or data that may be left behind by this server. It is best you do a thorough investigation of the environment after the de-install to ensure that nothing is left behind.

Cleaning up

So far, we have seen different ways to remove a dead Microsoft Exchange server. But your server continues to exist in the Active Directory because the connections were not removed. This means, you have a considerable amount of cleanup to do before you can remove the server.

• Log into your domain controller.
• Go to Windows run, and open the ADSIEdit tool again. This time, navigate to Configuration > CN = Configuration > CN=Services > CN = Microsoft Exchange > CN = <organization name> > CN=Administrative groups > CN=Exchange Server Administrative Groups > CN=Databases
• Identify the database containers that belonged to the server and delete them manually.

While removing mailboxes, take extra care because you sure don't want to delete a working mailbox. In case you do, you will have to re-create the user again using Active Directory Users & Computers.

After removing associated mailboxes, it is time to clean up the security settings. To do that,

• Launch Server Manager
• Navigate to Roles > Active Directory Domain Services > Active Directory users and Computers <domain>  > <domain> > Microsoft Exchange Security Groups.
• From the list of Exchange Servers, remove this server. Similarly, remove it from the list of Exchange Trusted Subsystem.

With this, your clean up should be complete.

However, if you notice, this is a long and arduous process with many pitfalls. So many things can go wrong and the chances for errors are high because many steps are involved.

Instead, a better option would be to restore backup or recover mailboxes with a third party tool like Stellar Repair for Exchange.

This tool repairs corrupt Exchange database files and restores the contents of mailboxes without any data loss. Its user friendly interface masks the complex process of recovery and restoration that is based on advanced algorithms.

The best part about this tool is the flexibility it offers to users like you. The recovered contents can be stored in any format such as PST, MSG, EML, HTML, RTF and PDF. As a result, exporting and viewing the contents is easy. In addition, this tool will display all the contents from a repaired mailbox and you can choose what contents should be recovered from this list.

Such a flexibility greatly enhances your user experience and makes this tool invaluable.