ERROR (GPOPEN) TRYING TO USE A FILE NUMBER ALREADY IN USE

I was tried to run an opt + freq calculation on water at NEVPT2/cc-pVDZ level of theory based on the tutorial for the CASSCF calculation in the Dalton manual using this input:

   Content of the .dal input file
 ----------------------------------

**DALTON INPUT
.OPTIMIZE
**WAVE FUNCTIONS
.HF
.MP2
.MCSCF
.NEVPT2
*SCF INPUT
.DOUBLY OCCUPIED
 3 1 1 0
*CONFIGURATION INPUT
.SYMMETRY
 1
.SPIN MULTIPLICITY
1
.INACTIVE
 1 0 0 0
.CAS SPACE
 4 2 2 0
.ELECTRONS
 8
**START
.SHIELD
.MAGNET
**PROPERTIES
.DIPGRA
.VIBANA
**END OF DALTON INPUT




   Content of the .mol file
 ----------------------------

BASIS cc-pVDZ
 Water geometry optimisation: NEVPT2/cc-pVDZ
 Project - Optimisation
Atomtypes=3
ZMAT
O   1 8.0
H   2 1 0.9 1.0
H   3 1 0.9 2 100.0 1.0

Unfortunately, I came across an error:

 ***************************************************************************************
 ****************** Output from **INTEGRALS input processing (HERMIT) ******************
 ***************************************************************************************


 - Using defaults, no **INTEGRALS input found

 Default print level:       -1

 Calculation of one-electron Hamiltonian integrals.
     
 Center of mass  (bohr):      0.008880851323      0.000000000000     -0.026428720411
 Operator center (bohr):      0.000000000000      0.000000000000      0.000000000000
 Gauge origin    (bohr):      0.008880851323      0.000000000000     -0.026428720411
 Dipole origin   (bohr):      0.008880851323      0.000000000000     -0.026428720411
         

--> ERROR (GPOPEN) TRYING TO USE A FILE NUMBER ALREADY IN USE

--> Offending UNIT number:    12
--> Name of offending file (if any): MOTWOINT
    
### Please report the problem on http://daltonforum.org
    
 Input parameter status : UNKNOWN
 Input parameter access :
 Input parameter format :  
    
--> Name of file already opened for this unit: MOTWOINT                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
    

 QTRACE dump of internal trace stack
       
 ========================
      level    module 
 ========================
         11    GPOPEN      
         10    HERCTL      
          9    HERMIT      
          8    GTNRGY      
          7    GTNPNT      
          6    NMDER       
          5    NUMDRV       
          4    RUNOPT      
          3    OPTMIN      
          2    DALTON      
          1    DALTON main 
 ========================
       
       
  --- SEVERE ERROR, PROGRAM WILL BE ABORTED ---
     Date and time (Linux)  : Thu Feb  5 14:36:20 2026
     Host name              : augustus
       
@ MPI MASTER, node no.:     0
@ Reason: ERROR (GPOPEN) TRYING TO OPEN A FILE ALREADY IN USE
    
  Total CPU  time used in DALTON: 10 minutes 33 seconds
  Total wall time used in DALTON:  2 minutes 42 seconds

As you can see, the output asks me to report the problem here, so this is what I am doing. I'm not quite sure what the problem is, and I'm not even sure if the final energy/geometry was genuinely optimised using NEVPT2 or just CASSCF. The full output should be attached below.

If anyone can help me out with this, I would appreciate it. I'm completely new to Dalton, so I don't have any idea how to debug the problem myself.

h2o-opt-nevpt2-dz.out