CI update from 1.7 to 2.0 getting Fatal error: Class 'CI_Controller' not found in CodeIgniter.php on line 210

[eluser]tdegryse[/eluser]
After a couple of days of changing code and trying things I've got the front page displaying correctly. However the other pages won't come up and return a 404. I think it's the routing..

Anyhow thanks a lot for your help,
Toon