Words of Warning
The recommended way to remove an Exchange server from your network is to properly uninstall it using the Exchange Server 2010 setup file. If the installation no longer exists, then there is also the option of installing a new server with the same name and restoring the original Exchange configuration. However, I have not explored this path as it appears to be much more time consuming.
The Active Directory also stores information about the mailboxes that were located on the lost server. To remove these, perform the following steps in the ADSI Edit tool:
- Navigate to CN=Configuration [domain] → CN=Services → CN=Microsoft Exchange → CN=[organization] → CN=Administrative Groups → CN=Databases
- Identify the Mailbox Database containers that belonged to the lost server and Delete them.
If there are multiple Exchange servers on the network, the Mailbox Database folders to delete can easily be identified by clicking on the folder and checking the Name field of the first entry, which should contain the name of the lost computer. Do not delete references to databases belonging to other Exchange servers!
Removing Security Settings
Now that the server is removed, some other settings need to be cleaned up as well. Perform the following additional steps on the domain controller:
- Launch Server Manager
- Navigate to Roles → Active Directory Domain Services → Active Directory Users and Computers [domain] → [domain] → Microsoft Exchange Security Groups
- Remove the computer from the members list of Exchange Servers
- Remove the computer from the members list of Exchange Trusted Subsystem.
If the computer was removed from the network altogether, you may also want to remove it from the Active Directory’s list of computers, as well as the DNS Server’s Forward Lookup Zones.
Removing AD Configuration
The list of Exchange servers on the domain is stored in the Active Directory configuration. Perform the following steps to remove the offending server:
- Log on to the network’s domain controller
- From the Start menu select Run… and enter adsiedit.msc to launch the ADSI Edit tool
- In the tool, right-click ADSI Edit and select Connect To…
- In the Connection Settings dialog under Select a well known Naming Context select Configuration and click OK
- Navigate to CN=Configuration [domain] → CN=Services → CN=Microsoft Exchange → CN=[organization] → CN=Administrative Groups → CN=Servers
- Right-click and Delete the container for the offending Exchange server.