CCL:G: symmetry constrained optimizations in Gaussian; IOp(2/16=2)

From: "Jonathan Stevens" <stevenje**udmercy.edu>
Subject: CCL:G: symmetry constrained optimizations in Gaussian; IOp(2/16=2)
Date: Mon, 12 Jun 2023 10:56:39 -0400
 Sent to CCL by: "Jonathan  Stevens" [stevenje~!~udmercy.edu]
 Hi,
 I am attempting an M062X geomerty optimization of CH3SH using M062X in
 Gaussian 16. I am trying to use Iop(2/16=2) to constrain the symmetry to the
 Cs point group.
 My input structure is symmetrical (cs point group)
 My control line is
 #N M062X/6-311+G(d,p) IOp(2/16=2) opt(z-matrix,calcfc) freq
 After initialization, this produces a very long error message.
 I have pasted the beginning below.
 Can anyone explain the error/issue?
 [pasted stuff below]
 Two-electron integral symmetry is turned on.
  One-electron integrals computed using PRISM.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 2.00D-06.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 4.00D-06.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 8.00D-06.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 1.60D-05.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 3.20D-05.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 6.40D-05.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 1.28D-04.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 2.56D-04.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 5.12D-04.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 1.02D-03.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 2.05D-03.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 4.10D-03.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 8.19D-03.
  Error in orthogonal basis= 8.41D-01 with    76 functions, increasing
 threshold to 1.64D-02.
  Error in orthogonal basis= 8.41D-01 with    75 functions, increasing
 threshold to 3.28D-02.
  Error in orthogonal basis= 8.41D-01 with    74 functions, increasing
 threshold to 6.55D-02.
  Error in orthogonal basis= 8.41D-01 with    70 functions, increasing
 threshold to 1.31D-01.
  Error in orthogonal basis= 8.41D-01 with    65 functions, increasing
 threshold to 2.62D-01.
  Error in orthogonal basis= 8.41D-01 with    57 functions, increasing
 threshold to 5.24D-01.
  Error in orthogonal basis= 8.41D-01 with    42 functions, increasing
 threshold to 1.05D+00.
  Error in orthogonal basis= 8.41D-01 with    24 functions, increasing
 threshold to 2.10D+00.
  Error in orthogonal basis= 8.41D-01 with    10 functions, increasing
 threshold to 4.19D+00.
  Error in orthogonal basis= 8.41D-01 with     4 functions, increasing
 threshold to 8.39D+00.
  Error in orthogonal basis= 8.41D-01 with     2 functions, increasing
 threshold to 1.68D+01.
  FileIO operation on non-existent file.
  FileIO: IOper= 2 IFilNo(1)=  -685 Len=           0 IPos=           0 Q=
 184545936
  dumping /fiocom/, unit = 1 NFiles =    84 SizExt =    524288 WInBlk =
 512
                    defal = F LstWrd =      873984 FType=2 FMxFil=10000
  Number              0             0             0             0
 0             0
  Base           311041        338471        432213        309773
 146943        267652
  End            312137        344247        537363        310752
 146944        267653
  End1           312137        344247        537363        310752
 146944        267653