Fatal error: Uncaught Error: Class "Symfony\Component\Mime\Encoder\Base64Encoder" not found in C:\xampp\htdocs\adminlte3\vendor\symfony\mime\Encoder 2\Base64MimeHeaderEncoder.php:17 Stack trace: #0 {main} thrown in C:\xampp\htdocs\adminlte3\vendor\symfony\mime\Encoder 2\Base64MimeHeaderEncoder.php on line 17