# Software inconsistency error: unimplemented potential modifier **URL:** \ **Category:** User discussions\ **Created:** [November 27, 2024, 6:13am UTC](https://gromacs.bioexcel.eu/t/software-inconsistency-error-unimplemented-potential-modifier/10645 "2024-11-27T06:13:47Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![RahulS](https://avatars.discourse-cdn.com/v4/letter/r/b9e5f3/32.png) [@RahulS](https://gromacs.bioexcel.eu/u/RahulS)\ **Post date:** [November 27, 2024, 6:13am UTC](https://gromacs.bioexcel.eu/t/software-inconsistency-error-unimplemented-potential-modifier/10645/1 "2024-11-27T06:13:47Z")
GROMACS version: 2020.5 GROMACS modification: Yes/No Here post your question gmx mdrun -v -deffnm min0 Reading file min0.tpr, VERSION 2020.5 (single precision) NOTE: Parallelization is limited by the small number of atoms, only starting 1 thread-MPI ranks. You can use the -nt and/or -ntmpi option to optimize the number of threads. Can not increase nstlist because an NVE ensemble is used 1 GPU selected for this run. Mapping of GPU IDs to the 1 GPU task in the 1 rank on this node: PP:0 PP tasks will do (non-perturbed) short-ranged interactions on the GPU PP task will update and constrain coordinates on the CPU Using 1 MPI thread Non-default thread affinity set, disabling internal thread affinity Using 32 OpenMP threads * * * Program: gmx mdrun, version 2020.5 Source file: src/gromacs/mdlib/forcerec.cpp (line 869) Software inconsistency error: unimplemented potential modifier I am getting error while running, Free Energy Calculations: Methane in Water but i am running for protein-ligand complexes @jalemkul