Fatal error: Uncaught Error: Call to undefined function Magento\Framework\Encryption\Adapter\some_function() in /var/www/html/vendor/magento/framework/Encryption/Adapter/Mcrypt.php:172 Stack trace: #0 /var/www/html/vendor/magento/framework/Encryption/Encryptor.php(452): Magento\Framework\Encryption\Adapter\Mcrypt->decrypt('\x9D\x9D\x15\xB9\xDA\xFA\xFD\x9D') #1 /var/www/html/vendor/magento/module-config/Model/Config/Backend/Encrypted.php(111): Magento\Framework\Encryption\Encryptor->decrypt('PayPal') #2 /var/www/html/vendor/magento/framework/App/Config/MetadataConfigTypeProcessor.php(133): Magento\Config\Model\Config\Backend\Encrypted->processValue('PayPal') #3 /var/www/html/vendor/magento/framework/App/Config/MetadataConfigTypeProcessor.php(152): Magento\Framework\App\Config\MetadataConfigTypeProcessor->processScopeData(Array) #4 /var/www/html/vendor/magento/framework/App/Config/PostProcessorComposite.php(36): Magento\Framework\App\Config\MetadataConfigTypeProcessor->process(Array) #5 /var/www/html/generated/code/Magento/ in /var/www/html/vendor/magento/framework/Encryption/Adapter/Mcrypt.php on line 172