You want to attempt to undelete a file that you previously deleted.
Using a graphical user interface
Files that you delete with Windows Explorer can be restored using the recycle bin:
This assumes that you didn't use the Shift+Del key combination to delete the file or haven't emptied the recycle bin since the file was deleted. One problem with this method is that the recycle bin captures only files deleted from Explorer. None of the files that are deleted over the network, via a command prompt, or with a script are sent to the recycle bin.
Using downloadable software
The Sysinternals Fundelete tool can be used as a replacement for the recycle bin. It works just like the recycle bin except it does more. The recycle bin icon on the desktop is replaced with a Fundelete Bin icon. The Fundelete Bin captures any type file deletion that occurs on the computer. And just as with the recycle bin, you can restore files contained in the Fundelete Bin.
Fundelete hasn't been updated since 2000, so if you are looking for something that is more recently updated, Executive Software makes a product that is similar to Fundelete with even more features, called Undelete. Unlike Fundelete, you have to pay for Undelete. For more information, visit: http://www.undelete.com.
MS KB 136517, "How the Recycle Bin Stores Files"