Problem: The client was experiencing an 'Internal Server Error' when accessing the English or German sections of their multilingual website using WPML. This error did not occur in the Italian section. Solution: We recommended checking and updating the .htaccess file as it might get overwritten during updates of WordPress, themes, or plugins, which can remove WPML's rules. We provided a guide to properly configure the .htaccess file for WPML. You can find the guide here: https://wpml.org/faq/why-is-htaccess-getting-overwritten-with-the-language-folder-on-my-wpml-website/. After applying the solution from our documentation and restoring the language format settings as they were before, the issue was resolved.
Please note that this solution might be irrelevant if it's outdated or not applicable to your case. 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 the problem persists, please open a new support ticket at WPML support forum.
