SMS provides and checks the SOFTWARE\Microsoft\SMS\Applications key under HKEY_CURRENT_USER in the Registry for ISV application launching. SMS also provides and checks the same key under HKEY_LOCAL_MACHINE, which contains a single value, Version, that allows SMS to handle Registry changes.
Applications registered under HKEY_LOCAL_MACHINE are available to all SMS users; applications registered under HKEY_CURRENT_USER are available only to the user who registered the application.
Note Administrator access is required to modify keys under HKEY_LOCAL_MACHINE.