If you are a Windows user, you have probably noticed from time to time that a file (or folder) will get locked by a process and you cannot determine what process has locked it. This might keep you from writing to a file, but, more often it will keep you from deleting a file or a folder. I have stumbled across a great little tool, Who Lock Me, that integrates with Windows Explorer (aka My Computer) which will allow you to right click on any file or folder and the select “Who Lock Me? …” and it will tell you which process has a lock that file or folder. This tool is invaluable.