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How to unhide file extensions for known file types!


How do I change Windows settings for hiding the file extensions of known file types?


This question was answered on October 18, 2002. Much of the information contained herein may have changed since posting.

A file extension helps your computer know what program is associated with a specific file

For example, a Microsoft Word document has a ".doc" extension while an Excel spreadsheet has a ".xls" extension By default, Windows hides these extensions in e-mail attachments, when browsing the files in My Computer or through the Windows Explorer to reduce the confusion for new users.

This default setting is also how virus writers try to fool people into opening a file that is actually a virus or worm They incorporate a double file extension such as 'airplane.jpg.exe' which will appear as 'airplane.jpg' for those that have not changed their default settings.

Once you tell Windows not to hide the extension of known file types, spotting obvious or suspicous virus or worm files becomes much easier, since they would have two extensions.

To change the default setting to show all file extensions:

1 Double-click the My Computer icon from the Desktop

2 Click the 'View' menu in Windows 9x and the 'Tools' menu in 2000/XP then select "Folder Options..." from the menu that appears

3 Click the View tab

4 Uncheck the "Hide file extensions for known file types" check box (To uncheck a check box, just click it.)

5 Click OK

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Posted by Ken of Data Doctors on October 18, 2002