# Error in user input: Invalid input values Required option was not provided **URL:** \ **Category:** User discussions\ **Tags:** mdrun\ **Created:** [January 9, 2025, 9:41pm UTC](https://gromacs.bioexcel.eu/t/error-in-user-input-invalid-input-values-required-option-was-not-provided/10991 "2025-01-09T21:41:46Z")\ **Posts on this page:** 2\ **Page:** 1
**Author:** ![guadalupe](https://avatars.discourse-cdn.com/v4/letter/g/76d3ee/32.png) [@guadalupe](https://gromacs.bioexcel.eu/u/guadalupe)\ **Post date:** [January 9, 2025, 9:41pm UTC](https://gromacs.bioexcel.eu/t/error-in-user-input-invalid-input-values-required-option-was-not-provided/10991/1 "2025-01-09T21:41:46Z")
GROMACS version: GROMACS modification: Yes/No Here post your question I have a problem with the NPT equilibration step Previous command gmx grompp -f npt.mdp -c nvt.gro -t nvt.cpt -r nvt.gro -p topol.top -n index.ndx -o ntp.tpr Command line: gmx mdrun -v -deffnm npt * * * Program: gmx mdrun, version 2021.4-Ubuntu-2021.4-2 Source file: src/gromacs/options/options.cpp (line 179) Function: void gmx::internal::OptionSectionImpl::finish() Error in user input: Invalid input values In option s Required option was not provided, and the default file ‘topol’ does not exist or is not accessible. The following extensions were tried to complete the file name: .tpr I’m using the npt file provided in Github ([GROMACS/mdp\_files/npt\_equil.mdp at master · UWPRG/GROMACS · GitHub](https://github.com/UWPRG/GROMACS/blob/master/mdp_files/npt_equil.mdp)) and the topol file is saved in my workspace as topol.top The solutions provide in other discussions isn´t workink to fix my problem ---
**Author:** ![Karis](https://avatars.discourse-cdn.com/v4/letter/k/ed8c4c/32.png) [@Karis](https://gromacs.bioexcel.eu/u/Karis)\ **Post date:** [January 10, 2025, 5:21am UTC](https://gromacs.bioexcel.eu/t/error-in-user-input-invalid-input-values-required-option-was-not-provided/10991/2 "2025-01-10T05:21:37Z")
There’s a typo, ‘-o ntp.tpr’ in your first command