CakePHP showing blank page

In the end it was APC cache conflicts between multiple Cakes on the same server.

All I had to do was change $prefix in config.php and it worked.

Cakephp can show also blank page, if you have some component included in your controller and it contains error, and if for some reason debug does not work(though debug level in core.php is 2 or 3 ) in your component , it just shows blank page.

Happened to me when I had a constant defined, did not notice this and defined another one with the same name.

const VISIBLE = 1;
const DELETED = 0;
const VISIBLE = 1;

A few years later I will add a comment here:

This would mean there was a syntax error, make sure u display these.