By default windows always comes with file extensions hidden. But this feature is not good for your system security.

Because many times when you download file from internet or some other sources ( CD, PenDrive ), some file comes with virus.
Generally you don’t understand, because this file normally display like .jpg. Bmp .mp3, and its extension is hide (windows always comes with file extensions hidden)
Example:
Normal file: mysongs.mp3
Virus file: mysongs.mp3.exe

You think this is mp3 but this is not true this is only primary name of your file; its secondary name (file extension) is hidden.

Now you click this file and your computer becomes infected by virus. So always first check your file extension then run.

So turn on file extension
1.Open control panel and click classic view ( left side of control panel )
2.Open folder options
3.Click view tab and go to advanced settings:(in centre )
4.Unselect Hide extensions for known file types check box

Tags: security, virus