The action can’t be completed because the file is open in noderunner.exe
You may get ‘The action can’t be completed because the file is open in noderunner.exe’ error in Exchange Server 2013 when you try to delete a mailbox database.
This error is due to the noderunner.exe – a process of the Host Controller Service putting a lock on the index files. To remove the lock you need to restart the HostControllerService.
Try deleting the folder and the contents after service restart. It should now work.