When a file is saved or created using a Windows application, the file is given a three-letter extension. The extension--such as .txt--is used by the operating system to identify the type of file and the application that should be used to open it. However, it is also possible to create a file with no extension by removing an existing extension from a file. Configure Windows to display file extensions, then remove an extension from a file that you prefer not to have an extension.
Open a Windows Explorer window. This can be done quickly by pressing the Windows logo and "R" keys at the same time, then typing "Explorer" in the window that appears.
Click "Tools," then click "Folder Options" if your computer has Windows XP installed. If you are running Windows Vista or 7, click "Organize," then click "Folder and Search Options."
Select the "View" tab. Remove the check from the box labelled "Hide extensions for known file types," then click "OK." The three-letter extension is now displayed at the end of each file name.
Locate the file that you prefer not to have an extension. Right-click the file, then click "Rename." The name of the file becomes highlighted, and a blinking cursor appears.
Press the "End" key on the keyboard, or press the right-arrow key until the blinking cursor appears to the right of the file extension.
Press the "Backspace" key four times, or more for longer file extensions (which are not common). The file extension and the period separating it from the file name are now erased.
Press "Enter" to save the new file name. The file no longer has an extension.
A file extension should not be removed without a specific reason for doing so. Windows will ask which application you want to use to open a file with no extension every time the file is opened, because a file extension is used to identify the type of the file.