WHMCS Tags troubleshooting-article Troubleshoot and resolve last request failed: invalid SASL argument errors. Troubleshoot and resolve Google reCAPTCHA or hCaptcha® Invalid Site Key errors. Troubleshoot and resolve issues with Invalid VAT number format errors for various countries during checkout. Troubleshoot and resolve issues with The supplied VAT number is not valid errors while collecting Value-Added Tax (VAT) for the United Kingdom. Troubleshoot and resolve errors and warnings about invoice immutability. Troubleshoot and resolve issues with missing taxes on invoices. Troubleshooting and resolving Key Generation Failed: (XID xxxxxx) You do not have the feature “sslmanager” errors while selling SSL certificates through WHMCS MarketConnect. Troubleshoot and resolve failing database backups for large WHMCS installations. Troubleshoot and resolve Failed to remove legacy modules errors. Troubleshoot and resolve the ionCube Encoder® error that makes the Admin Area return HTTP 500 after you update WHMCS. Troubleshoot and resolve A license key is required. errors during installation. Troubleshoot and resolve cPanel & WHM or WP Squared server profile errors. Troubleshoot and resolve Invalid Key errors while using the Software Licensing addon. Troubleshoot and resolve the Software Licensing addon generating a new key with each request. Troubleshoot and resolve Remote Check Failed errors with the Software Licensing addon module. Troubleshoot and resolve Unable to accept the template: the following limitations are exceeded errors. Troubleshoot and resolve connection errors in Live Chat. Troubleshoot and resolve button and display issues in Live Chat. Troubleshoot and resolve `License Invalid` errors and problems logging in to Live Chat. Troubleshoot and resolve Incorrect Server/Host errors in Live Chat.