I just updated from Drupal 8.1.x to 8.2.5 manually, I delete core and vendor folders first, and all the roots files from my instalaion, but When I try to acces the update.php I get this error,
Fatal error: Class 'Drupal\Core\Database\Connection' not found in /home/<username>/public_html/blog/core/lib/Drupal/Core/Database/Driver/mysql/Connection.php on line 22
The site is in a PHP 7.0 server, I checked the settings.php file and it is correct I am trying Drupal for the first time, and I don´t know what to do. Installation was working fine. Somebody Knows how to fix this issue? Thank you.