Problem: If you're unable to activate WPML and encounter a 500 Ajax error indicating a critical error, it might be due to a database collation issue. Specifically, the error message might show a fatal error related to an invalid collation for the character set 'utf8mb4'. Solution: We recommend updating your database collation to a supported one, such as utf8mb4_unicode_520_ci, and converting existing tables to use this new collation. Detailed guidance on this can be found at WPML Minimum Requirements. If you're unsure about how to make these changes, please contact your hosting provider for assistance. After updating the collation: • Try activating WPML again. It should activate without issues once the collation is corrected. If you still cannot access your site while the collation issue is being resolved, you can temporarily disable WPML via FTP: 1. Navigate to /wp-content/plugins/ 2. Rename the sitepress-multilingual-cms folder (e.g., add _disabled to the name) 3. Access your WordPress admin again 4. Rename the folder back once access is restored Please ensure to back up your database before making any changes.
If this solution does not resolve your issue or seems irrelevant due to being outdated or not applicable to your case, we highly recommend checking related known issues at WPML Known Issues, verifying the version of the permanent fix, and confirming that you have installed the latest versions of themes and plugins. If further assistance is needed, please open a new support ticket.
