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ALL ABOUT FILE EXTENSIONS
by Ray DeCosta


Q. I have heard that I should never open an EXE file unless someone I trust has sent it to me. What does that mean?

A. An "EXE file" means it's an "executable file" which can run on your computer and does something to your system. Its actions can be good (installing a program or driver you want) or bad (installing a virus or other malware). The term EXE refers to the file's extension which is a three- or four-character long suffix attached to the file's name. This would look something like "MyFileName.EXE"

The extension will give you a clue as to what the file is. For instance, JPG or JPEG refers to a picture file, MP3 is an audio file, HTM or HTML is an Internet file, DOC or DOCX is a Word document file, etc. Windows uses the extension to decide which program should open the file when you click on it.

However, when you buy a Windows computer it is almost always set up to hide the file extensions from being displayed in My Computer or Computer depending on your operating system. This may allow you to unknowingly click on an infected EXE file while you are thinking, for instance, that it's a picture.

To see the file extensions, in Computer or My Computer, go to Tools -- Folder Options and click on the View tab. Scroll down to where you see "Hide extensions for known file types", uncheck the box and then hit "OK." The next time you look at your files, their extensions will be visible.

Published: Courier 2/6/11 - Page 5C