ICONPACKAGE (IconPackage Theme File)
The ICONPACKAGE System file format
ICONPACKAGE files are created using a program of the same name. The IconPackager software by Stardock is used to create different icons for the Windows operating system. The ICONPACKAGE file is a theme file that stores all kinds of information about the icons used in a theme. Among others, it helps to map the icons in the theme to the icons used by Windows by default. Clicking on the ICONPACKAGE will load the corresponding IconPackager theme and thus change the visual style of the Windows user interface.
Technical details of ICONPACKAGE files
There are several other file formats that are used together with the ICONPACKAGE file. Usually, these are icon files with the ICO extension or a whole icon library such as an ICL file. Before IconPackager version 5, another file format was used to store theme files for the program, namely IPTHEME. Furthermore, compressed theme files with the IP extension are also closely related to the ICONPACKAGE format.