RegistryDelete – PB Docs 2018

key

A string whose value is the key in the system
registry you want to delete or whose value you want to
delete.

To uniquely identify a key, specify the list
of parent keys above it in the hierarchy, starting with the root
key. The keys in the list are separated by
backslashes.

valuename

A string containing the name of a value in the
registry. If the specified key does not have a subkey, specifying
an empty string deletes the key and its named
values.