VMS Help UIL, Compile Time Errors, PREVIOUS_DEF  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  ERROR:  The name marked by  the  message  was  used  in  a  previous
  declaration.   UIL  requires  that the names of all objects declared
  within a module be unique.

  USER  ACTION:   Check  for  a  misspelling.   If   the   module   is
  case-sensitive,  the  spellings  of  names  in  declarations  and in
  references must match exactly.