# Error with the .prm file / bonds

**URL:** https://gromacs.bioexcel.eu/t/error-with-the-prm-file-bonds/1623
**Category:** User discussions
**Created:** [February 19, 2021, 9:17pm UTC](https://gromacs.bioexcel.eu/t/error-with-the-prm-file-bonds/1623 "2021-02-19T21:17:06Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![Amar\_Kumar](https://avatars.discourse-cdn.com/v4/letter/a/ecc23a/32.png) [@Amar\_Kumar](https://gromacs.bioexcel.eu/u/Amar_Kumar)
#### Post date: [February 19, 2021, 9:17pm UTC](https://gromacs.bioexcel.eu/t/error-with-the-prm-file-bonds/1623/1 "2021-02-19T21:17:06Z")

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![mdp](https://europe1.discourse-cdn.com/flex017/uploads/bioexcel1/original/1X/50ee88956dbb46e296115b167b445da18f64baf6.png) ![prm](https://europe1.discourse-cdn.com/flex017/uploads/bioexcel1/original/1X/753c24613f9353e1f4771e698c250a3253306569.png)

 ![error_01](https://europe1.discourse-cdn.com/flex017/uploads/bioexcel1/original/1X/0bc72d3dfbf07fab7498cdb75308cec23e8351c7.png) GROMACS version:  
GROMACS modification: Yes/No  
Here post your question

I have generated the topology using the CGenFF server and the penalty scores were ok (around 1), but then I get an error message when trying to solvate my system.

Files related to the question are attached. Thank you.

 ![error_01](https://europe1.discourse-cdn.com/flex017/uploads/bioexcel1/original/1X/0bc72d3dfbf07fab7498cdb75308cec23e8351c7.png) [ions.mdp](https://gromacs.bioexcel.eu/uploads/short-url/ys5IXQIh9iszAaYC7M8hvIGQjfR.mdp) (1021 Bytes)

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### Author: ![jalemkul](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/jalemkul/32/18_2.png) [@jalemkul](https://gromacs.bioexcel.eu/u/jalemkul)
#### Post date: [February 19, 2021, 10:34pm UTC](https://gromacs.bioexcel.eu/t/error-with-the-prm-file-bonds/1623/2 "2021-02-19T22:34:07Z")

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Make sure you have the latest version of the CHARMM36 port from the MacKerell lab. The atom type is part of the current force field, which indicates that you’re using an old version of the port, likely with an old version of CGenFF.

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### Author: ![Amar\_Kumar](https://avatars.discourse-cdn.com/v4/letter/a/ecc23a/32.png) [@Amar\_Kumar](https://gromacs.bioexcel.eu/u/Amar_Kumar)
#### Post date: [February 19, 2021, 11:51pm UTC](https://gromacs.bioexcel.eu/t/error-with-the-prm-file-bonds/1623/3 "2021-02-19T23:51:59Z")

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Thank you for the response. I’ll check that.