.ICL File Extension

Contains a collections of icons that can be used to replace existing icons; may be applied to Windows shortcuts (such as .LNK files), but not to actual program files.

To change the icon of a file, right-click the file, select "Properties," and click the "Change Icon" button. You can then browse to an ICL file and view the available icons in the library. If you find an icon you like, you can select it and assign it to the file.