Fatal error: Uncaught Error: Class 'Symfony\Component\Mime\Encoder\Base64Encoder' not found in C:\xampp73\htdocs\web\vendor\symfony\mime\Encoder\Base64ContentEncoder.php:19 Stack trace: #0 {main} thrown in C:\xampp73\htdocs\web\vendor\symfony\mime\Encoder\Base64ContentEncoder.php on line 19