VMS Help CC, Messages, ENUMUSED  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 Message        <Context> the enumerator name "<name>" has been used
                previously.

 Description    The specified enumerator name has been previously
                declared as something other than an enumerator.

 User Action    Either use a different enumerator name or remove the
                previous declaration of the name.