Today I came across an issue where I had to determine if a server was sucessfully removed from a SharePoint Farm. When starting Central Admin on the application server it launched the Configuration Wizard asking to join or create a new farm. When launching SharePoint Powershell it returned the message “Farm is inaccessible”. The farm consisted out of mutliple application and webservers. Central Admin on one of the applicationservers didn’t list the server which I had to remove so all looked like it was succesfully removed.
However there is a way to know for sure if a server is succesfully removed from a SharePoint Farm. The solution can be found in the registry of the applicationserver. If it is succesfully removed from the farm you will not be able to find the connection string for it’s SharePoint configuration database.
The key can be found in \\HKEY_LOCAL_MACHINE\Software\Microsoft\Shared Tools\Web Server Extensions\14.0\Secure where the key will be named ConfigDb. If there is no key listed you can conclude the server has been succesfully removed from the farm. If there is still a key listed feel free to remove it!