CakePHP cannot find UsersController

I have been following the blog tutorial on cakephp.org and I had adding and editing the posts table working fine. I wanted to add a user login but I am having trouble when following the tutorial. When I run my application now I keep getting the error:

Error: UsersController could not be found.

Error: Create the class UsersController below in file: app/Controller/UsersController.php

I know the controller is definitely there, I followed naming conventions, and I can’t find any errors in the code for UsersController.php or anything else. Does anyone have any idea why this may be happening?

EDIT: clearing caches don’t seem to be the problem. All that is there is an empty text file.

Thanks,
Jon

Answer

Check file permissions, it should be readable by everyone.

Clear your cache in /app/tmp/cache/models, /app/tmp/cache/persistent