Library inside library

[eluser]tonanbarbarian[/eluser]
you will have to give more information
post the code of the controller and if possible the library that is being loaded

one tip is to make sure that library files are named correctly.
recommended is the first character of the name is in uppercase and the rest in lower
i.e. libraries/Auth.php
and when you load the library you can use either upper or lower case for the name, but the name of the object created will always be all lower case

Code:

$this->load->library('Auth');
or
$this->load->library('auth');
should both work but the call to the library will always then be lowercase
$this->auth->check();
but not
$this->Auth->check(); // WILL NOT WORK

I also noticed from your previous example that you were calling your class CI_abc or similar.
Do not...
Only core CI classes are prefixed with CI
You should just call it abc or whatever
i.e.

Code:

class Auth {
}