VMS Help Sys Parameters, SSINHIBIT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    SSINHIBIT controls whether system services are inhibited (1)
    (on a per-process basis). By default, system services are not
    inhibited (0).

    This special parameter is used by Compaq and is subject to
    change. Do not change this parameter unless Compaq recommends
    that you do so.