# Problem with files being written and read by different versions of GROMACS

**URL:** <https://gromacs.bioexcel.eu/t/problem-with-files-being-written-and-read-by-different-versions-of-gromacs/2959>\
**Category:** User discussions\
**Created:** [October 13, 2021, 10:31pm UTC](https://gromacs.bioexcel.eu/t/problem-with-files-being-written-and-read-by-different-versions-of-gromacs/2959 "2021-10-13T22:31:46Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![sbandeka](https://avatars.discourse-cdn.com/v4/letter/s/85f322/32.png) [@sbandeka](https://gromacs.bioexcel.eu/u/sbandeka)\
**Post date:** [October 13, 2021, 10:31pm UTC](https://gromacs.bioexcel.eu/t/problem-with-files-being-written-and-read-by-different-versions-of-gromacs/2959/1 "2021-10-13T22:31:46Z")

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GROMACS version: 2021.3  
GROMACS modification: Yes/No

Hello all, GROMACS convert-tpr is currently giving me this error:

To clarify, I am running this through SBGrid where I have forced the setting of “2020.2\_cu9.2.88” as my grimaces version using my SBGrid configuration file.

Has anyone seen anything similar before?

gmx convert-tpr, version 2021.3  
Executable: /programs/x86\_64-linux/gromacs/2021.3\_cu10.2/bin/…/…/gromacs-2021.3-lzui/bin/gmx  
Data prefix: /programs/x86\_64-linux/gromacs/2021.3\_cu10.2/bin/…/…/gromacs-2021.3-lzui  
Working dir: /project2/arac/…  
Command line:  
gmx convert-tpr -s protein\_md\_1us.tpr -o protein\_md\_1us\_ana.tpr

Reading file protein\_md\_1us.tpr, VERSION 2020.2 (single precision)  
Note: file tpx version 119, software tpx version 122  
/programs/share/capsules/lib/job.sh: line 120: 42440 Segmentation fault “SB\_EXECFILE" "@”

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**Author:** ![alevilla](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/alevilla/32/439_2.png) [@alevilla](https://gromacs.bioexcel.eu/u/alevilla)\
**Post date:** [October 14, 2021, 1:46pm UTC](https://gromacs.bioexcel.eu/t/problem-with-files-being-written-and-read-by-different-versions-of-gromacs/2959/2 "2021-10-14T13:46:50Z")

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Hi,  
maybe this post helps

> [@Reading tpx file version 119 with version 103 program](https://gromacs.bioexcel.eu/t/reading-tpx-file-version-119-with-version-103-program/703):
>
> GROMACS version: 2020.2 I am following the “KALP-15 in DPPC” tutorial on my computer with GROMACS 2020.2, and I try to run the NPT equilibration in parallel on a cluster of my department, whose GROMACS is version 5.1.2. I submit my job and the output file reads: Fatal error: reading tpx file (npt.tpr) version 119 with version 103 program Is this because the tpr file produced by a latter version of GMX cannot be read by an older GMX? If so, how to deal with the problem?

\Alessandra

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**Author:** ![ebriand](https://dub1.discourse-cdn.com/flex017/user_avatar/gromacs.bioexcel.eu/ebriand/32/2314_2.png) [@ebriand](https://gromacs.bioexcel.eu/u/ebriand)\
**Post date:** [October 20, 2021, 1:52pm UTC](https://gromacs.bioexcel.eu/t/problem-with-files-being-written-and-read-by-different-versions-of-gromacs/2959/3 "2021-10-20T13:52:10Z")

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There is a bug when calling convert-tpr with only `-s` and `-o` (possibly since 2021.3).

Depending on which function of convert-tpr you want to use, there may be some workarounds:

- If you want to extend the runtime, use option `-until`, `-extend`, `-nsteps` (see help: `-h` for details on what they do).
- If you want to extract a subset, or, if you want to update the tpr version but do nothing otherwise (that is, exactly what you seem to be doing with that command line), you have to specify an index file also. You can select group 0 to output the whole system. For use in script, you can use something like `echo 0 | gmx convert-tpr -s in.tpr -o out.tpr -n index.ndx`