"An Error Was Encountered" no error details - $this->load->_ci_autoloader();

[eluser]Unknown[/eluser]
Hello,

I have an issue with an app we created with CI2. It works perfectly on a number of servers but a new environment is throwing an error. Problem is the error has no details - "An Error Was Encountered" is all i get. Debugging has lead me to $this->load->_ci_autoloader(); in system/core/controller.php. The error is thrown at this point.

My question is - what could cause this? I assume it is related to the server config but not sure what I need to change.

Further details - I am using modular extensions with a custom controller (MY_Controller in application/core) that calls the the CI_Controller constructor.

Thanks for any help.

[eluser]Unknown[/eluser]
Update - the logs show it loads all the helpers but stops when trying to load the libraries. Odd.