Display File Extensions

By default, most versions of Windows hide the file extension for known file types. Compare these screen shots of the same files in the same folder:

The upper image shows the actual filenames. The lower one shows them filtered, with the known file extensions removed.

Now imagine you've been told to rename the active Hal1FACP.yw5 file to something else, and to rename the Hal1FACP.yw5.bak file to .yw5

In the upper window it's easy. In the lower window you're left scratching your head. The 'Hal1FACP.yw5' file in the lower window is really 'Hal1FACP.yw5.bak', and the 'Hal1FACP' file is really 'Hal1FACP.yw5'

Obviously the default option to hide known file extensions is confusing, and therefore we're going to switch it off. The following instructions work on all versions of Windows.

First, open any Explorer window. Next, click the Tools menu item followed by Folder Options. (On Vista/Windows 7 you may need to click Organise - Layout then tick Menu Bar.)

When the window opens, select the View tab. Now compare your display to the screen below, where the option you need to untick has been circled. Once it's de-selected, click Ok to close the window.

Now your system will show the full and correct filenames, and you'll be able to identify and rename files as you please.