HKCR
This variable is the alias for the HKEY_CLASSES_ROOT registry root and is used to abbreviate the registry hive name HKEY_CLASSES_ROOT in registry paths.
Usage
Used internally by InstallMate. You can refer to this variable as <HKCR>. It is normally used as part of a registry path, as in <@<HKCR>\...remainder of path...>. This variable is read-only; do not try to change it.