/sys$common/syshlp/helplib.hlb FORTRAN, Error Messages, Compilation Errors, VARNOTASS  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  SEVERITY:  E

  MESSAGE TEXT:  Variable not assigned label by ASSIGN statement

  EXPLANATION:  A variable was found in a context that required an
  assigned label (such as in an assigned GOTO statement or as the
  format specifier of an I/O statement), but no ASSIGN statement was
  found that assigned a label to that variable.

  This error commonly occurs if you use an arithmetic assignment
  statement instead of the ASSIGN statement.  If the program
  executes, the result is unpredictable.