Today I have been busy removing the Release Preview of Exchange 2013 from a number of my lab servers. All was going well until I came to removing Exchange from a couple of Exchange 2013 DAG Servers – where I was presented with the following error message:
Error: This computer is a member of a cluster. It must be removed from the database.
Prior to my attempting to remove Exchange I had removed all database copies that had been associated with the server.
Luckily the solution was very simple.
In order to resolve this error message, open a PowerShell command window and type in the following commands:
This will list all of the Exchange Servers that are associated with the Failover Clustering service – identify the name of the Exchange server that you are trying to remove Exchange from – then type:
Cluster node <Node Name> /Evict
When the node has been removed from the cluster type in the following PowerShell cmdlet
You can then close the PowerShell window and return to the Exchange 2013 RP setup process and click on the “Retry” button – and which should then result in the removal prerequisites completing correctly.