I am using Gromacs MD simulation for protein-ligand complex using the following command after NVT Equilibration :

gmx grompp -f npt.mdp -c nvt.gro -t nvt.cpt -r nvt.gro -p topol.top -n index.ndx -o npt.tpr

But it shows the following error:

Fatal error:

Too many warnings (1).

If you are sure all warnings are harmless, use the -maxwarn option

However, I have already downloaded the NPT script provided by the tutorials in MDP file format before the run.

Please, help me to solve the problem...