VMS Help LBR Routines, LBR$DELETE_DATA, Condition Values Returned  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    LBR$_ILLCTL        Specified library control index not valid.
    LBR$_INVRFA        Specified RFA not valid.
    LBR$_LIBNOTOPN     Specified library not open.
    LBR$_STILLKEYS     Keys in other indexes still point at the
                       module header. Therefore, the specified module
                       was not deleted.