Upgrading from 3.x.x to 3.4.5 gives an 500 error on both frontend and backend.
The fix was to clear the OpCache manually and re-run frontend and backend. No need for restoring a backup.
Here is my recommandation for the next version of Joomla.
Insert this code before the upgrade is started:
Code: Select all
if (extension_loaded('Zend OPcache')) opcache_reset();
I am manually doing it for my web clients that use OpCache on their sites.
With this little improvement you also avoid 500 errors when installing and upgrading extensions for Joomla.