If this template helps then use it. If not then just delete and start from scratch.
OS (e.g. Win10): macOS Big Sur
PsychoPy version (e.g. 2024.2.4 Py 3.8): 2023.2.3
**Standard Standalone Installation? yes
URL of experiment: Pavlovia
**Do you want it to also run locally? no
What are you trying to achieve?:
I uploaded the Psychopy experiment about a week ago and after some debugging it worked as intended. The experiment makes use of 4 short mp4 movie files. The experiment ran in Pilot and Run mode without issues, I even started data collection successfully, until one or two days ago. Now, when starting the experiment, an error message appears indicating that an mp4 resource could not be downloaded. I had not changed anything in the code or files/folders of the experiment prior to this error message.
What did you try to make it work?:
I tried renaming the mp4 files, placing them in different locations (the files are currently placed in a /Videos/ folder within the experiment folder, which worked fine previously for this and other experiments). I reuploaded all experiment files. However, the error remains.
Link to the most relevant existing thread you have found:
I could not find a thread or topic similar to my case.
What specifically went wrong when you tried that?:
Error message reads:
Unfortunately we encountered the following error:
- when setting up a preload queue
- unable to download resource: Videos/Plants_.mp4 (Videos/Plants_.mp4)
Try to run the experiment again. If the error persists, contact the experiment designer.
Hello @VincentVanDeVen
Did you empty the cache or used a private window after you redid everything? Is it always the same file that can’t be downloaded?
Best wishes Jens
Dear Jens,
Thanx for replying. Yes, I cleaned browser cache. I did not try private browser, but online participants using different browsers got yhr same error.
I also condulted Chrone’s developer tool to see ehere the error occurs in launching the experiment but could not find anything beyond the error message of not finding the file.
Is it perhaps possible that some server update or other background process interferes with the pavlovia experiment?
Kind regards,
Vincent.
Hello @VincentVanDeVen
I do not know anything about any server updates. This is not my area.
Usually the error comes from a misspelling of the filename, file extension or path. Therefore, I asked whether this is only file that is affected or whether other files are also affected.
Best wishes Jens
Dear Jens,
That would make sense. However, the experiment ran without issue a week ago, with filenames or references unchanged. The ouzzling thing is then that at some point the code raised a new error. I also thought that somehow filenames or folders perhaps changed, but I checked filename and location in several ways, without finding the issue. The error always referred to the first movie in a list, stopping the program and therefore not making it to other movies. I cannot verify if other movies would show the same error, but I would think that they would.
Awkward, isnt it?
I’ll check later today if the error persists.
Kind regards,
Vincent.
Hello @VincentVanDeVen
If it always the first file in randomized list, you could make the list sequential. If it is the first file of a sequential list, you could change the first file.
Best wishes Jens
Dear Jens,
Thanks for your suggestion. The list of videos is loaded sequentially by default. I also replaced the first file in the list with another of the movie files and the same error was raised for the replaced file. Also, as the experiment worked previously, I think that the problem is not with the movie files themselves.
Kind regards,
Vincent.
Hello @VincentVanDeVen
Do you mind to provide access to the repository?
Best wishes Jens
Sure, no problem. Do I do this by setting “Experiment visibility” to public?
Dear Jens,
I just saw that the experiment is running again. When starting, I do not get the error about movie file downloading anymore and the experiment continues as it did previously. I was not able to find the problem, but apparently it works again.
Thanks for your help, I hope the incidental “glitch” does not come back.
Kind regards,
Vincent.