Windows - Show hidden files and extensions

Why display the extensions?

When extensions are hidden, an infected file may seem harmless.
Example: a simple image file (.jpg) may be actually an executable file (.exe).
For the same reason it may be useful to display hidden files but beware: among these hidden files, there are the system files. Never delete them without inquiring about their usefulness.

To view extensions

Windows XP

• Open Windows Explorer.
• Go to the "Tools" menu and select "Folder Options"
• Select the "View" tab.
• Uncheck "Hide extensions for file types is known" and click "Apply:

Windows Vista/7

• Open Explorer
• Go to the "Organize" menu > Folder and Search Options:
• Select the "View" tab.
• Uncheck "Hide extensions for file types is known" and click "Apply"

Windows 8

• Open Explorer and select the "View" tab:
• In the "Show/Hide" section, check "File name extensions

Solution via the registry

• Open the Registry Editor
• Go to "HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Advanced".
• Create (or modify) a new string value and name it "HideFileExt".
• Set it's value to "0".

To display hidden files and folders

• Use the same methods as above, but this time, select "Show hidden files and folders".
• For Windows 8, you must check "Hidden Items"