Problem: The client was experiencing a 500 internal server error on the English version of their website. Solution: 1. We recommended ensuring that the client is using the latest versions of their theme and plugins. 2. We advised the client to re-save Permalinks by navigating to Settings >> Permalinks and clicking the Save Changes button. 3. We suggested clearing all types of cache from the site/server to see if the issue would be resolved. 4. If the problem persisted, we provided a link to an errata page that might offer a workaround: https://wpml.org/errata/htaccess-is-rewritten-with-language-folder/
Please note that the solution provided might be irrelevant due to being outdated or not applicable to your case. If the issue persists, we highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix, and confirming that you have installed the latest versions of themes and plugins. If you still need assistance, please open a new support ticket with us.
