Thanks for your further comments and instructions.
I tested the same scripts (CHARMM input & Slurm sbatch) using a trajectory generated by CHARMM and ran into the same fatal error. So I suspect it is more likely that the command 'traj read" does not work for MPI CHARMM.
One workaround is to replace 'traj read' with 'coor DYNA first XX nunit 1 begin @frame stop @frame skip ?SKIP'. And it worked.
I am not sure if CHARMM c45b1 could resolve the issue, but I will try.
Thanks again and stay safe.
All the best
Last edited by shane yue; 11/01/20 08:25 PM.