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File Extensions

Viewing File Extensions on Windows

SUMMARY: Help protect yourself from accidentally opening rogue files by forcing Explorer to show all files' extensions.

Depending on how your Windows computer is setup, file extensions may be hidden. Instead of seeing files containing a period and 1-4 character extensions, all you see are the filenames without the extensions. Or, some files may have extensions, but not all of them.

For safety reasons, and to learn more about file formats, you should configure Windows to show all file extensions.

Although the instructions for showing file formats differ depending on the version of Windows you are running, they are generally the following:

1. Open any folder on your machine.
2. Choose "Tools" - "Folder Options".
3. Click the "View" tab.
4. Uncheck "Hide extensions for known types".
5. Click "OK" to close the dialog box.