illegal string position

  Explanation:  The service completed successfully.  However,  one
  of  the  character-position  parameters to a string manipulation
  routine pointed to  a  character-position  that  is  before  the
  beginning  of  the  input string or that is after the end of the
  input string.

  User Action:  Ensure that any  character-position  parameter  is
  greater  than  zero  and less than or equal to the length of the
  input string.