# Error in openmc.run() command

**URL:** <https://openmc.discourse.group/t/error-in-openmc-run-command/2414>\
**Category:** User Support\
**Created:** [October 31, 2022, 12:39pm UTC](https://openmc.discourse.group/t/error-in-openmc-run-command/2414 "2022-10-31T12:39:19Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Dalia](https://avatars.discourse-cdn.com/v4/letter/d/a698b9/32.png) [@Dalia](https://openmc.discourse.group/u/Dalia)\
**Post date:** [October 31, 2022, 12:39pm UTC](https://openmc.discourse.group/t/error-in-openmc-run-command/2414/1 "2022-10-31T12:39:19Z")

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Hello,

I’m running the code in here:  
[https://docs.openmc.org/en/v0.8.0/pythonapi/examples/post-processing.html](https://docs.openmc.org/en/v0.8.0/pythonapi/examples/post-processing.html)  
and all cells ran fine but when I run: openmc.run() I get this error:

 ![image](https://global.discourse-cdn.com/free1/uploads/openmc/original/2X/e/e6f5e81d3bccba40fabfb7afe6a3cf804e51d4a0.png)  
Thanks a lot for your help!

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**Author:** ![Shimwell](https://yyz2.discourse-cdn.com/free1/user_avatar/openmc.discourse.group/shimwell/32/3876_2.png) [@Shimwell](https://openmc.discourse.group/u/Shimwell)\
**Post date:** [October 31, 2022, 6:20pm UTC](https://openmc.discourse.group/t/error-in-openmc-run-command/2414/2 "2022-10-31T18:20:21Z")

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Just for anyone reading this in the future, Dalia visited the [drop in session](https://openmc.discourse.group/t/openmc-monthly-drop-in-session-dates-2022/1629) and we fixed this by adding a MeshFilter to the code.