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Show File Extensions on Windows XP/2000

Have you wondered where the file extensions went on your Windows machines?
By default, Windows operating system does not display the extension on all files. The extension is the name of the files behind the last dot, which helps identify which application should be used to open the file. For example, files with a .doc will open with Microsoft Word. Hiding the file extension makes it difficult to rename files, and makes it easy for virus writers to hide the nature of malicious files.
You will need to view the file extensions so that you can rename files, in particular if you would receive an attachment that has been renamed due to the protective e-mail filters on high risk attachment types.
See Protective E-mail Filters for more information on which attachments are currently blocked by the mail server filters.

To view these extensions for all files:

  1. Double-click My Computer
  2. Click the Tools menu item and select Folder Options
  3. Click on the View tab
  4. Uncheck or deselect the box next to " Hide file extensions for known file types"
  5. Click OK