# Warning in Grompp command

**URL:** <https://gromacs.bioexcel.eu/t/warning-in-grompp-command/5652>\
**Category:** User discussions\
**Created:** [January 26, 2023, 4:26am UTC](https://gromacs.bioexcel.eu/t/warning-in-grompp-command/5652 "2023-01-26T04:26:37Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![akash6912](https://avatars.discourse-cdn.com/v4/letter/a/3be4f8/32.png) [@akash6912](https://gromacs.bioexcel.eu/u/akash6912)\
**Post date:** [January 26, 2023, 4:26am UTC](https://gromacs.bioexcel.eu/t/warning-in-grompp-command/5652/1 "2023-01-26T04:26:37Z")

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GROMACS version:  
GROMACS modification: Yes/No  
Here post your question  
while running the following command  
gmx grompp -f em.mdp -c 1\_ions.gro -p topol.top -o em.tpr  
i am getting the following issue  
WARNING 1 [file topol.top, line 104856]:  
You are using Ewald electrostatics in a system with net charge. This can  
lead to severe artifacts, such as ions moving into regions with low  
dielectric, due to the uniform background charge. We suggest to  
neutralize your system with counter ions, possibly in combination with a  
physiological salt concentration.

[Files](https://drive.google.com/drive/folders/1-GTYobx8Rce4tTaDWytkTkHLHbbR_KJU?usp=sharing)