This is occurring whenever I press "Save Customer" in the manage customers area in the Admin panel:
Fatal error: Class 'Mage' not found in /app/code/core/Mage/Core/Model/Resource/Session.php on line 108
This error has come about after upgrading from
Magento 22.214.171.124 to
I realise this question may be a bit vague but all I'm after is some information on why I may be getting this error. I have done an amount of googling in the hope that this might be a common error, however no luck so far.
Any help in relation to how to track where this error is coming from or anyone with any knowledge on common problems with this sort of thing would be greatly appreciated.