# ERROR 1 \[file topol.top, line 30229\]: No default Proper Dih. types

**URL:** <https://gromacs.bioexcel.eu/t/error-1-file-topol-top-line-30229-no-default-proper-dih-types/6852>\
**Category:** User discussions\
**Created:** [July 18, 2023, 10:37am UTC](https://gromacs.bioexcel.eu/t/error-1-file-topol-top-line-30229-no-default-proper-dih-types/6852 "2023-07-18T10:37:39Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![faaiza](https://avatars.discourse-cdn.com/v4/letter/f/df788c/32.png) [@faaiza](https://gromacs.bioexcel.eu/u/faaiza)\
**Post date:** [July 18, 2023, 10:37am UTC](https://gromacs.bioexcel.eu/t/error-1-file-topol-top-line-30229-no-default-proper-dih-types/6852/1 "2023-07-18T10:37:39Z")

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GROMACS version: 2021.4  
GROMACS modification: no  
Here post your question can anyone tell me how to solve this error i got after the gmx grompp -f ions.mdp -c solv.gro -p topol.top -o ions.tpr command.

I’m also getting  
ERROR 15 [file fix.itp, line 40]:  
Atomtype N5M not found

i created ligand Itp file using swissparam

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<div class="post-metadata">

**Author:** ![Karis](https://avatars.discourse-cdn.com/v4/letter/k/ed8c4c/32.png) [@Karis](https://gromacs.bioexcel.eu/u/Karis)\
**Post date:** [July 20, 2023, 6:31am UTC](https://gromacs.bioexcel.eu/t/error-1-file-topol-top-line-30229-no-default-proper-dih-types/6852/2 "2023-07-20T06:31:31Z")

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Could you provide the contents of your topol.top file and the ligand itp file? The issue might be that the atoms were being called before they were actually defined.

Also, could you copy-paste the terminal output you got (warnings, error messages, notes) when you entered the command? And were there any errors/warnings/notes you got in any of the pervious steps or was this command the first step that received anything out of the ordinary?