Few things in life are more frustrating than finding a file you want to do something with is "locked" by some program. Most of the time, you can't figure out what the real culprit actually is, leaving you locked out, burning daylight. File & Folder Unlocker makes it a snap to unlock any file so you can get on with your day.
File & Folder Unlocker is free, tiny (just 35KB) and totally portable; there's no installation required. Just search for the file that's locked -- or if you know where it is, just drag the icon into the program window -- and you'll see which processes are locking your document. You can then sever the connection and move on.
I've found this utility especially handy for those times when I copy a bunch of files to the desktop, do something with them (like print or e-mail them) and then, when I try to delete the files afterwards, Windows gives me some cryptic message that the files are still in use somewhere, somehow. Now I can laugh at the puny error message and have my way with the files. [via Make Use Of]