# Nonexistent parameter (plCompanionCalibration) in error message

**URL:** <https://discourse.psychopy.org/t/nonexistent-parameter-plcompanioncalibration-in-error-message/43174>\
**Category:** Builder\
**Tags:** pavlovia\
**Created:** [December 6, 2024, 7:11pm UTC](https://discourse.psychopy.org/t/nonexistent-parameter-plcompanioncalibration-in-error-message/43174 "2024-12-06T19:11:53Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Liberos](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/liberos/32/5902_2.png) [@Liberos](https://discourse.psychopy.org/u/Liberos)\
**Post date:** [December 6, 2024, 7:11pm UTC](https://discourse.psychopy.org/t/nonexistent-parameter-plcompanioncalibration-in-error-message/43174/1 "2024-12-06T19:11:53Z")

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**OS** (e.g. Win10): Win10  
**PsychoPy version** (e.g. 1.84.x): 2024.02.02  
**Standard Standalone? (y/n)** Y  
**What are you trying to achieve?:** Run same experiment working on Mac M1

**What did you try to make it work?:**  
Experiment runs on Mac M1 no problem. It has PsychoPy 2023. I need to run the experiment on the Windows machine, but keep getting a weird " Nonexistent parameter (plCompanionCalibration)" but that parameter is not something I coded (maybe a default somewhere, but a code search found nothing).

I tried using different versions of PsychoPy, since there was a discrepancy.  
I tried to reset the display parameter.  
I tried to turn off the refresh rate detector.  
I restarted the computer and PsychoPy.  
I deleted and reinstalled from the Mac.

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**Author:** ![wakecarter](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/wakecarter/32/5753_2.png) [@wakecarter](https://discourse.psychopy.org/u/wakecarter)\
**Post date:** [December 6, 2024, 9:51pm UTC](https://discourse.psychopy.org/t/nonexistent-parameter-plcompanioncalibration-in-error-message/43174/2 "2024-12-06T21:51:26Z")

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Open the psyexp file in a text editor and search for plCompanionCalibration.

Does your Mac installation have a plugin that’s missing from the Windows one?

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**Author:** ![Liberos](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/liberos/32/5902_2.png) [@Liberos](https://discourse.psychopy.org/u/Liberos)\
**Post date:** [December 7, 2024, 7:25pm UTC](https://discourse.psychopy.org/t/nonexistent-parameter-plcompanioncalibration-in-error-message/43174/3 "2024-12-07T19:25:03Z")

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I was able to find that word when opening the file in a textpad. It suggested an experiment setting somewhere.

I found that this plCompanionCalibration had been activated (turned “on”) in a checkbox despite that I had never used or had the problem on the first device. I turned it off, saved, and the error was resolved.

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**Author:** ![Liberos](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/liberos/32/5902_2.png) [@Liberos](https://discourse.psychopy.org/u/Liberos)\
**Post date:** [December 17, 2024, 12:23am UTC](https://discourse.psychopy.org/t/nonexistent-parameter-plcompanioncalibration-in-error-message/43174/4 "2024-12-17T00:23:35Z")

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Just fyi, this happened in two more experiments when I updated my PsychoPy to 2024.2.3. The settings added this new parameter and defined it, despite that it did not exist before. It does just need to be turned off.