Problem: When WPML is enabled and a visitor switches language to /en/, WordPress rewrites .htaccess with:
RewriteBase /en/
and routes requests to /en/index.php. There is no physical /en/ directory as language URLs are virtual. This causes REST API endpoints (/wp-json/, /wp-json/wp/v2/) to break and results in intermittent server-level 404 errors. Disabling WPML stops this behavior, and locking .htaccess prevents the rewrite but is only a workaround.
Solution: This issue is likely related to a known problem where .htaccess gets overwritten with the language folder. We recommend you ensure to have a full website backup and apply the solution outlined in the erratum. You can find more details and guidance here: Why is .htaccess getting overwritten with the language folder on my WPML website?
If this solution does not resolve your issue or seems outdated, we highly recommend checking related known issues at https://wpml.org/known-issues/, verifying the version of the permanent fix, and confirming that you have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.
Problem: You might be facing two separate issues with WPML on your site. First, when WPML is enabled, no menus are visible in WP-Admin under Appearance → Menus, and the WPML Menu Sync hangs indefinitely. Second, enabling WPML and switching the language to /en/ causes WordPress to rewrite .htaccess with 'RewriteBase /en/' and route requests to /en/index.php, leading to broken REST API endpoints and intermittent 404 errors.
Solution: For the menu visibility issue, it appears to be related to the User Registration & Membership plugin, which includes flawed WPML compatibility code. You can resolve this by disabling a part of that plugin's code. Add the following to your site's functions.php or via a code snippet plugin:
This modification might affect the User Registration & Membership plugin, so it's advisable to contact their support for a more permanent solution. They should use the WPML developer API, specifically the wpml_permalink filter.
For the .htaccess rewrite issue, please provide more details by describing the problem again, so we can create a new support ticket to address it specifically.
Please note that the solutions provided might become outdated or may not directly apply to your case. If these steps do not resolve your issues, 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.
