Uninstall Exchange server 2013 from WIN 2012R2 Server- Its domain controller

Hi Team, i need assistance in deleting/removing exchange server from 2012 r2 domain controller.

Tried uninstalling the same but getting the following error.

Error:
The following error was generated when "$error.Clear(); 
          if (Get-Service W3Svc* | ?{$_.Name -eq 'W3Svc'})
          {
            Set-Service W3Svc -StartupType Automatic
            Start-SetupService -ServiceName W3Svc
          }
        " was run: "Service 'WAS' failed to reach status 'Running' on this server.".

Appreciate your help on this 

This is bit urgent !

Thanks In Advance