Fatal error: Class Zend\Stdlib\Parameters contains …. in Magento 2
To solve this problem run following commands:
1. php bin/Magento setup:upgrade
2. php bin/Magento setup:static-content:deploy
3. php bin/Magento cache:clean
4. php bin/Magento cache:flush
If still exist your problem, please restart your web server.
I hope solve this issue.