Upgrading from 1.3 to 1.4.1.10

[lee-chilli]

I'm trying to upgrade from 1.3 to 1.4.1.10.

 

I've read the manual upgrade for this and followed and gotten this error

Fatal error: Class 'ObjectModel' not found in /var/www/vhosts/boxchilli.co/httpdocs/kittykit/2test/classes/Configuration.php on line 28

 

 

I've look and read what's on the fourm and found nothing which can help me resolve this issue.

 

 

Any help would be great.