Site Admin area broken after upgrade

[Contender]

I did a composer upgrade from 2.06 to 2.07 and now get this message when trying to access the site admin pages! Doesn't even load the login screen.

Fatal error: Class 'Magento\Framework\Code\Generator\Autoloader' not found in /var/sites/e/***.co.uk/public_html/vendor/magento/framework/ObjectManager/DefinitionFactory.php on line 104

[OST Agency]

You can check this link,

http://magento.stackexchange.com/questions/91087/magento-2-admin-url-not-working-and-loaded-frontend...

You may get some help

[Francis Kim]

It's possible that it's a permissions or a file ownership issue. Have you tried running chmod and changing the owner to the Apache/Nginx user?