# ParaView Catalyst warns instead of raising an error when the script is not found

**URL:** https://discourse.paraview.org/t/paraview-catalyst-warns-instead-of-raising-an-error-when-the-script-is-not-found/17543
**Category:** In Situ Support
**Created:** [May 1, 2026, 3:00pm UTC](https://discourse.paraview.org/t/paraview-catalyst-warns-instead-of-raising-an-error-when-the-script-is-not-found/17543 "2026-05-01T15:00:39Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![Alexandre\_Minot](https://discourse.paraview.org/user_avatar/discourse.paraview.org/alexandre_minot/32/7132_2.png) [@Alexandre\_Minot](https://discourse.paraview.org/u/Alexandre_Minot)
#### Post date: [May 1, 2026, 3:00pm UTC](https://discourse.paraview.org/t/paraview-catalyst-warns-instead-of-raising-an-error-when-the-script-is-not-found/17543/1 "2026-05-01T15:00:39Z")

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Dear all,

If the catalyst script is not found, ParaView displays

```auto
[pvbatch.0]vtkInSituInitialization:295 WARN| File/path does not exist and not in PYTHONPATH: 'my_paraview_interface'. Skipping.

```

and the ParaView Catalyst `initialize` call returns `catalyst_status_ok`.

I really think this should be an error. What does the community thinks?

I tried to reproduce this with the examples, but I can no longer find the Catalyst2 examples in the source code. Not sure where they went. In particular, the links here are broken: [Examples for Simulation Developers — ParaView Documentation 5.12.0 documentation](https://docs.paraview.org/en/v5.12.1/Catalyst/examples.html)

Thanks,  
Alexandre

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### Author: ![ben.boeckel](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.paraview.org/u/ben.boeckel)
#### Post date: [May 1, 2026, 7:52pm UTC](https://discourse.paraview.org/t/paraview-catalyst-warns-instead-of-raising-an-error-when-the-script-is-not-found/17543/2 "2026-05-01T19:52:33Z")

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That makes sense to me. Cc: @Jeff_Lee

The examples now live: [https://gitlab.kitware.com/paraview/catalyst-examples](https://gitlab.kitware.com/paraview/catalyst-examples)

Cc: @Bob_Obara for the examples bit.

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### Author: ![Jeff\_Lee](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/j/8797f3/32.png) [@Jeff\_Lee](https://discourse.paraview.org/u/Jeff_Lee)
#### Post date: [May 3, 2026, 12:33am UTC](https://discourse.paraview.org/t/paraview-catalyst-warns-instead-of-raising-an-error-when-the-script-is-not-found/17543/3 "2026-05-03T00:33:38Z")

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Agree, this should be an adaptor choice whether to continue the simulation if the script isn’t found. We can return an error code specific to that condition so the adaptor can decide whether to abort or continue.

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### Author: ![Alexandre\_Minot](https://discourse.paraview.org/user_avatar/discourse.paraview.org/alexandre_minot/32/7132_2.png) [@Alexandre\_Minot](https://discourse.paraview.org/u/Alexandre_Minot)
#### Post date: [May 4, 2026, 12:53pm UTC](https://discourse.paraview.org/t/paraview-catalyst-warns-instead-of-raising-an-error-when-the-script-is-not-found/17543/4 "2026-05-04T12:53:28Z")

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Yes, I agree. We could consider returning `catalyst_status_error_not_found` so we don’t need a new Catalyst release.

[https://gitlab.kitware.com/paraview/paraview/-/work\_items/23270](https://gitlab.kitware.com/paraview/paraview/-/work_items/23270)