Library /sys$common/syshlp/basichelp.hlb Compile time errors, LETDIRSYN  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  ERROR - A %LET directive contains a  syntax  error,  for  example,  an
  invalid  lexical  identifier.   Use  the  correct  syntax for the %LET
  directive.