# Issues Running Basic Hello World Experiment Online – psychojs-2024.2.1post4.js Not Loading Properly

**URL:** <https://discourse.psychopy.org/t/issues-running-basic-hello-world-experiment-online-psychojs-2024-2-1post4-js-not-loading-properly/41231>\
**Category:** Online experiments\
**Created:** [August 30, 2024, 12:26pm UTC](https://discourse.psychopy.org/t/issues-running-basic-hello-world-experiment-online-psychojs-2024-2-1post4-js-not-loading-properly/41231 "2024-08-30T12:26:46Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![hanit.galili](https://avatars.discourse-cdn.com/v4/letter/h/d26b3c/32.png) [@hanit.galili](https://discourse.psychopy.org/u/hanit.galili)\
**Post date:** [August 30, 2024, 12:26pm UTC](https://discourse.psychopy.org/t/issues-running-basic-hello-world-experiment-online-psychojs-2024-2-1post4-js-not-loading-properly/41231/1 "2024-08-30T12:26:46Z")

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I’m trying to run a very basic “Hello World” experiment online, but I’m facing some issues.

1. **Localhost Issue:** The experiment is not working locally. The issue seems to be with a file called `psychojs-2024.2.1post4.js`. Instead of being a JS file, it appears as HTML code. This causes errors when `index.html` tries to load it as a JS file.
2. **Pavlovia Issue:** When I try to run the experiment from Pavlovia, I encounter another problem. The `lib` folder does not seem to sync to Pavlovia, so when `index.html` tries to access `./psychojs-2024.2.1post4.js`, it can’t be found.

**Setup Details:**  
PsychoPy v.2024.2.1post4

Any help or guidance to resolve these issues would be highly appreciated!

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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:** [August 30, 2024, 1:44pm UTC](https://discourse.psychopy.org/t/issues-running-basic-hello-world-experiment-online-psychojs-2024-2-1post4-js-not-loading-properly/41231/2 "2024-08-30T13:44:20Z")

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This should be fixed in PsychoPy 2024.2.2 or you can install the Python 3.8 version of 2024.2.1

> [@Cannot run simple experiment on Pavlovia (returns 404 not found error)](https://discourse.psychopy.org/t/cannot-run-simple-experiment-on-pavlovia-returns-404-not-found-error/34397/3):
>
> Hi there, Apologies, this is an error (on my part) caused by adding the label “post4” which I thought was not included in the internal writing of the file. If you install the python 3.8 version of the installer, which is simply 2024.2.1 (not post4) that version should generate your files just fine. We’ll make a 2024.2.2 release soon with this more fixed in both python versions best wishes, Jon

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**Author:** ![hanit.galili](https://avatars.discourse-cdn.com/v4/letter/h/d26b3c/32.png) [@hanit.galili](https://discourse.psychopy.org/u/hanit.galili)\
**Post date:** [September 18, 2024, 6:58am UTC](https://discourse.psychopy.org/t/issues-running-basic-hello-world-experiment-online-psychojs-2024-2-1post4-js-not-loading-properly/41231/3 "2024-09-18T06:58:24Z")

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Thank you!  
I downgraded to version 2024.2.1, and everything is working perfectly now.