The error loading preloads: could not find renderer typically occurs while working with the “Jupyter Notebook extension when there might be an error with the installation or compatibility of the extension.”
How to fix it?
To fix the error loading preloads: could not find renderer, press the ctrl+shift+P command and Reload a window. If you just don’t see the bar without any error, disable the Jupyter Notebook renderers extension, test, and re-enable it.
Another fix is to Roll back to a previous, stable version of an extension, which is often a good troubleshooting step when encountering issues with the latest version.
Software updates can sometimes introduce new bugs or incompatibilities, and using an older version can be an excellent temporary fix while waiting for those issues to be resolved in future updates.
For anyone else encountering a similar issue, the steps to roll back to a previous version of a Jupyter extension may vary slightly depending on whether you’re using Jupyter Notebook or Jupyter Lab, but the principle remains the same:
- Go to the Jupyter extension tab: This is usually accessible from the Jupyter interface.
- Find the ‘Uninstall’ button: It is often located next to the extension you want to roll back.
- Click the down arrow next to ‘Uninstall’: This usually gives you more options.
- Choose ‘Install Another Version’: This will allow you to install a different extension version.
- Select a version from over a month ago: This is based on the original suggestion, assuming that older versions are more stable.
Alternate Solutions
Here are the alternate solutions:
Check Compatibility
Version Check: Ensure that the extension is compatible with the version of Jupyter Notebook or Jupyter Lab you are running.
Reinstall the Extension
Reinstall: Sometimes, simply reinstalling the extension can solve the issue.
For Jupyter Notebook:
jupyter nbextension install --py [extension-name]
For Jupyter Lab:
jupyter labextension install [extension-name]
Disable Other Extensions
Conflict Check: Sometimes, extensions can conflict with each other. Try disabling other extensions to see if that resolves the issue.
Update Packages
Ensure that all of your packages are up-to-date, especially Jupyter itself. You can update Jupyter and other Python packages using pip or conda.
That’s it!
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Krunal Lathiya is a seasoned Computer Science expert with over eight years in the tech industry. He boasts deep knowledge in Data Science and Machine Learning. Versed in Python, JavaScript, PHP, R, and Golang. Skilled in frameworks like Angular and React and platforms such as Node.js. His expertise spans both front-end and back-end development. His proficiency in the Python language stands as a testament to his versatility and commitment to the craft.