Hello, my name is Alfredo and I´m having the same issue with Odoo 17 saas while tring to use ENglish and ESpansih languages in the website.

I've tried upgrading the app and re-installing all localization apps. Same error

I've tried with Chrome, Chrome incognito and Microsoft Edge. I've deleted all cookies. Same error

I obtained this same list f naswers in Chat Gpt and went through it with success. 

Any other source of knowledge that we can explore??

In advance thank you, Alfredo

SOLVED !! :-) 

I detected a tax module for Spain PGCE that was creating the problem

How I did it? I created a asandbox duplicated database and started uninstalling modules trial-error till I found the cause

When you encounter an error like "Error while loading the localization. You should probably update your localization app first" while trying to install a French language on your Odoo website, it typically indicates an issue with the localization module or its configuration. Here's a step-by-step approach to troubleshoot and resolve the issue:

Steps to Resolve Localization Error in Odoo

1. Update Localization Modules

1. Check Installed Localization Modules:
   • Go to Apps.
   • Search for localization modules related to French (e.g., "French Localization").
2. Update Localization Modules:
   • Ensure that you have the latest version of the localization modules installed.
   • Click on the module and select Upgrade if an update is available.

2. Update Your Odoo System

1. Update Odoo to the Latest Version:
   • Sometimes, errors occur due to outdated versions. Make sure your Odoo instance is up-to-date.
   • You can update your Odoo system via the command line if you have access. Use commands like odoo -u all (for updating all modules) or odoo -u (for a specific module).
2. Check for Compatibility Issues:
   • Ensure that your Odoo version is compatible with the version of the localization module you are trying to install.

3. Verify Language Settings

1. Enable French Language:
   • Go to Settings > Translations > Languages.
   • Ensure that French is installed and set up. If not, add French as a language.
2. Apply Translations:
   • Go to Settings > Translations > Application Terms.
   • Make sure that French translations are applied.

4. Check Geolocation Configuration

1. Verify Geolocation Settings:
   • Go to Settings > Website > Geolocalization.
   • Ensure that geolocation is correctly configured. Sometimes, errors in geolocation settings can affect language settings.
2. Clear Cache:
   • Sometimes, clearing the cache can resolve unexpected issues. Clear your browser’s cache and restart your Odoo server.

5. Inspect Logs for Detailed Errors

1. Check Odoo Logs:
   • Inspect the Odoo server logs for more detailed error messages.
   • Logs are usually located in /var/log/odoo/odoo-server.log or similar locations depending on your installation.
2. Look for Specific Errors:
   • The logs might provide more information on what exactly is failing during the localization loading process.

6. Reinstall Localization Apps

1. Uninstall and Reinstall Localization Apps:
   • If updating doesn’t work, try uninstalling and then reinstalling the French localization module.

7. Seek Support

1. Odoo Community and Forums:
   • If the issue persists, consider reaching out to the Odoo community or forums for assistance. The community can offer advice based on similar experiences.
2. Contact Odoo Support:
   • If you have a support subscription, contact Odoo support directly for help with localization issues.

By following these steps, you should be able to address the error related to French localization and successfully install and configure the French language on your Odoo website.