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

  Illegal I/O channel (ERR=46)

  The program specified an I/O channel outside the legal range.  Specify
  I/O channels in the range 1 to 99, inclusive.