# ERROR 1 \[file dd.itp, line 198\]: No default Proper Dih. types

**URL:** <https://gromacs.bioexcel.eu/t/error-1-file-dd-itp-line-198-no-default-proper-dih-types/12117>\
**Category:** User discussions\
**Tags:** forcefield, mdp-parameters, mdrun, analysis-tools\
**Created:** [May 19, 2025, 6:23pm UTC](https://gromacs.bioexcel.eu/t/error-1-file-dd-itp-line-198-no-default-proper-dih-types/12117 "2025-05-19T18:23:24Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![Hindol](https://avatars.discourse-cdn.com/v4/letter/h/ecae2f/32.png) [@Hindol](https://gromacs.bioexcel.eu/u/Hindol)\
**Post date:** [May 19, 2025, 6:23pm UTC](https://gromacs.bioexcel.eu/t/error-1-file-dd-itp-line-198-no-default-proper-dih-types/12117/1 "2025-05-19T18:23:24Z")

</div>

I’m not sure how to resolve this issue. I generated the `.str` file using the online CGenFF platform (which I assume is up to date), but I’m having trouble figuring out how to fix the error.

ERROR 1 [file dd.itp, line 198]:  
No default Proper Dih. types

ERROR 2 [file dd.itp, line 200]:  
No default Proper Dih. types

ERROR 3 [file dd.itp, line 224]:  
No default Proper Dih. types

ERROR 4 [file dd.itp, line 226]:  
No default Proper Dih. types

Excluding 3 bonded neighbours molecule type ‘Protein\_chain\_A’  
Excluding 3 bonded neighbours molecule type ‘Other\_chain\_A2’  
Excluding 3 bonded neighbours molecule type ‘dd’  
Excluding 2 bonded neighbours molecule type ‘SOL’

NOTE 2 [file topol.top, line 55]:  
System has non-zero total charge: -1.000000  
Total charge should normally be an integer. See  
[Floating point arithmetic — GROMACS webpage https://www.gromacs.org documentation](http://www.gromacs.org/Documentation/Floating_Point_Arithmetic)  
for discussion on how close it should be to an integer.

There were 2 notes

* * *

Program: gmx grompp, version 2020.1-Ubuntu-2020.1-1  
Source file: src/gromacs/gmxpreprocess/grompp.cpp (line 1928)

Fatal error:  
There were 4 errors in input file(s)

## For more information and tips for troubleshooting, please check the GROMACS website at [Common Errors — GROMACS webpage https://www.gromacs.org documentation](http://www.gromacs.org/Documentation/Errors)

(base) hindol@hindol\_cha:/mnt/c/Users/hindo/Desktop/Academics/Internships/St. Xavier’s (Autonomous) college/Computational biology/MD Simulation/B. subtilis/1svi\_dd (Dimethyl diethylmalonate)$