File extension attributes in registry


There are two things you can do with any file extension, although I do not know how much useful they can be...
We can view the following keys in the registry;the first key (.lnk), which is the extension for the shortcut files, points to the second one (lnkfile).

HKCR\.lnk
HKCR\lnkfile

If we navigate to the second key (lnkfile), we can see two empty string (REG_SZ) values on the right when this key is selected:
  • IsShortcut
  • NeverShowExt

If we add those values to any desired file extension then two things happen:
  • A small arrow appears at the lower left corner of the icon (IsShortcut)
  • The file extension of the icon does not appear, regardless of the folder settings in the Control Panel (NeverShowExt)

Really, if you want to make fun, using this hint you can give the illusion that some icons on the desktop are shortcuts (while they are not).

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