In addition to files, tools on Windows might access or modify the system registry. Use the --emake-reg-roots command-line option to specify a key to mirror. You can specify more than one key by separating multiple entries with semicolons:
--emake-reg-roots=HKEY_LOCAL_MACHINE\Software\Foo; HKEY_LOCAL_MACHINE\Software\Bar
In addition, you can specify exception keys to not mirror the system registry by prefixing each key with a “ – ” character. For example:
--emake-reg-roots=HKEY_LOCAL_MACHINE\Software\Foo; -HKEY_LOCAL_MACHINE\Software\Foo\Base
which mirrors all keys and values under Foo except the keys in Foo\Base.
To ensure compatibility with Microsoft Visual Studio, the registry root specification automatically includes:
HKEY_CLASSES_ROOT;-HKEY_CLASSES_ROOT\Installer; -HKEY_CLASSES_ROOT\Licenses
Registry mirroring supports only HKEY_LOCAL_MACHINE (HKLM) and HKEY_CLASSES_ROOT (HKCR) registry keys.