# Error when setting up a preload queue in testing mode

**URL:** <https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354>\
**Category:** Online experiments\
**Created:** [March 24, 2025, 9:26am UTC](https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354 "2025-03-24T09:26:58Z")\
**Posts on this page:** 12\
**Page:** 1

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**Author:** ![semantic\_learning](https://avatars.discourse-cdn.com/v4/letter/s/b77776/32.png) [@semantic\_learning](https://discourse.psychopy.org/u/semantic_learning)\
**Post date:** [March 24, 2025, 9:26am UTC](https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354/1 "2025-03-24T09:26:58Z")

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It seems some people have had similar problems, but I haven’t found a solution that works yet…

I set up an online experiment that started working last week. There have been some issues with images that it’s supposed to show from the very beginning, but it’s worked to change all images from .jpg to .png files, and I was able to pilot the whole experiment last week. Now, it stopped working again, with the same error message.

 ![Urdu](https://us1.discourse-cdn.com/flex002/uploads/psychopy/original/3X/3/1/319a63d7665d2f6714c67b3e7e767e92d6ddb7b9.jpeg)

The experiment runs in PsychoPy, and it runs in js-mode in PsychoPy Builder in pilot mode, but not when I set it to testing mode, nor in Pavlovia.

In the experiment settings, I checked that the “output path” in the online settings is set to blank. I also checked that the relevant files are in the gitlab folder, which can be accessed via Pavlovia in the “view code” tab.

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**Author:** ![JensBoelte](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/jensboelte/32/9060_2.png) [@JensBoelte](https://discourse.psychopy.org/u/JensBoelte)\
**Post date:** [March 24, 2025, 10:08am UTC](https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354/2 "2025-03-24T10:08:59Z")

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Hello @semantic_learning

Does one of the following help?

> [@Wakefield's Daily Tips](https://discourse.psychopy.org/t/wakefields-daily-tips/43371/83#p-126242-online-errors-unknown-resource-1):
>
> Online errors: unknown resource This is one of the most common errors for experiments which run locally but fail online. In the case of a spreadsheet the name of the spreadsheet is mentioned twice. In the case of an image, you see the name of the image component (ImageStim) and the name of the file (resources). [image] [image] At the start of an online experiment you usually see a download bar for the resources. [image] However, at this stage PsychoPy only downloads files it can identify, e…

Best wishes Jens

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<div class="post-metadata">

**Author:** ![semantic\_learning](https://avatars.discourse-cdn.com/v4/letter/s/b77776/32.png) [@semantic\_learning](https://discourse.psychopy.org/u/semantic_learning)\
**Post date:** [March 24, 2025, 10:31am UTC](https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354/3 "2025-03-24T10:31:21Z")

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Thanks for the fast reply, Jens!

The proposed solution is basically to make sure that the files are listed in the “online” tab of the experiment settings, right?

Unfortunately, that doesn’t seem to help: The files are definitely there, but I still get the same error message (again, only in js run mode).

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**Author:** ![JensBoelte](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/jensboelte/32/9060_2.png) [@JensBoelte](https://discourse.psychopy.org/u/JensBoelte)\
**Post date:** [March 24, 2025, 10:45am UTC](https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354/4 "2025-03-24T10:45:13Z")

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Hello @semantic_learning

It is always Folie1.png?

> [@semantic\_learning](#):
>
> The proposed solution is basically to make sure that the files are listed in the “online” tab of the experiment settings, right?

Yes, you are correct.

Did you run the experiment in an incognito tab or flushed the cache after correcting any error?

Best wishes Jens

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<div class="post-metadata">

**Author:** ![semantic\_learning](https://avatars.discourse-cdn.com/v4/letter/s/b77776/32.png) [@semantic\_learning](https://discourse.psychopy.org/u/semantic_learning)\
**Post date:** [March 24, 2025, 11:09am UTC](https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354/5 "2025-03-24T11:09:23Z")

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Thanks for the response!

The browser deletes all history/cache after it is closed, so that doesn’t seem to be the issue.

I tried removing the first welcome screen, which is where Folie1.png is needed, but interestingly, still got the error message about Folie1.png. I don’t think it’s specific to this one image, though - I previously had the same problem with the same image files in .jpg format, and changing them to .png worked last week (i.e., I was able to run the experiment in Pavlovia), but over the weekend it stopped working again.

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<div class="post-metadata">

**Author:** ![JensBoelte](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/jensboelte/32/9060_2.png) [@JensBoelte](https://discourse.psychopy.org/u/JensBoelte)\
**Post date:** [March 24, 2025, 12:09pm UTC](https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354/6 "2025-03-24T12:09:14Z")

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Hello @semantic_learning

> [@semantic\_learning](#):
>
> I tried removing the first welcome screen, which is where Folie1.png is needed, but interestingly, still got the error message about Folie1.png.

Then the code still refers to Folie1.png or uses a cached version of your experiment.

Best wishes Jens

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<div class="post-metadata">

**Author:** ![semantic\_learning](https://avatars.discourse-cdn.com/v4/letter/s/b77776/32.png) [@semantic\_learning](https://discourse.psychopy.org/u/semantic_learning)\
**Post date:** [March 24, 2025, 12:26pm UTC](https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354/7 "2025-03-24T12:26:19Z")

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Thanks for the response! So the issue could be that, whenever I run the experiment, it refers to a previous version of the experiment where there is no image file called “Folie1.png”?

Any idea how to check or fix this? The github folder associated with the Pavlovia experiment does have the image file. Deleting the Pavlovia experiment, re-generating the .py and .js-files and re-uploading everything doesn’t work. Neither does deleting the browser history and cache.

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<div class="post-metadata">

**Author:** ![JensBoelte](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/jensboelte/32/9060_2.png) [@JensBoelte](https://discourse.psychopy.org/u/JensBoelte)\
**Post date:** [March 24, 2025, 1:00pm UTC](https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354/8 "2025-03-24T13:00:21Z")

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Hello @semantic_learning

I mean that somewhere in your experiment you make a reference to Folie1.png. Check the py-code to find the relevant line of code, identify the routine and delete the reference from the component via the Builder. Have you deleted Folie1.png from the list of **Online Resources**?

Best wishes Jens

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<div class="post-metadata">

**Author:** ![semantic\_learning](https://avatars.discourse-cdn.com/v4/letter/s/b77776/32.png) [@semantic\_learning](https://discourse.psychopy.org/u/semantic_learning)\
**Post date:** [March 24, 2025, 1:40pm UTC](https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354/9 "2025-03-24T13:40:13Z")

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Thanks for the suggestions! Well, I don’t really want to remove Folie1.png: it’s my first instruction screen. I did so for the previous post to see what would happen (in response to your question “It is always Folie1.png?”).

The issue is that, for some reason, the image doesn’t seem to be findable in running js-mode. It stops the experiment from running…

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<div class="post-metadata">

**Author:** ![JensBoelte](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/jensboelte/32/9060_2.png) [@JensBoelte](https://discourse.psychopy.org/u/JensBoelte)\
**Post date:** [March 24, 2025, 1:54pm UTC](https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354/10 "2025-03-24T13:54:33Z")

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Hello @semantic_learning

Do you mind sending me Folie1.png?

Best wishes Jens

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<div class="post-metadata">

**Author:** ![semantic\_learning](https://avatars.discourse-cdn.com/v4/letter/s/b77776/32.png) [@semantic\_learning](https://discourse.psychopy.org/u/semantic_learning)\
**Post date:** [March 24, 2025, 2:06pm UTC](https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354/11 "2025-03-24T14:06:56Z")

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Sure, here it is!

 ![Folie1.PNG](https://us1.discourse-cdn.com/flex002/uploads/psychopy/original/3X/8/4/8412639aaaf6a991d163b9ac3bbac7100b8c5348.png)

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<div class="post-metadata">

**Author:** ![JensBoelte](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.psychopy.org/jensboelte/32/9060_2.png) [@JensBoelte](https://discourse.psychopy.org/u/JensBoelte)\
**Post date:** [March 24, 2025, 2:34pm UTC](https://discourse.psychopy.org/t/error-when-setting-up-a-preload-queue-in-testing-mode/44354/12 "2025-03-24T14:34:07Z")

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Hello @semantic_learning

The file name is **Folie1.PNG** and not **Folie1.png**.

Best wishes Jens