Getting Error after uploading in server

It is best not to use mcrypt, it is abandonware, has not been updated in years mcrypt has many outstanding bugs dating back to 2003. The mcrypt-extension is deprecated will be removed in PHP 7.2. Instead consider using defuse (https://github.com/defuse/php-encryption) or RNCryptor (https://github.com/RNCryptor), they provide a complete solution and are being maintained and are correct.