Cannot Access Admin Backend

Our website has been up and running for months. Then, one morning, I received the following message while attempting to login to the admin backend.

An internal error happened in the script, please contact webmaster for details

I am able to pull the following error message from the error logs in the DB:

Code:

log_id: 4699
    user_id: NULL
      time: 2013-04-25 13:34:26
        url: /enroll/admin-auth/index
remote_addr: 69.165.175.102
  referrer: https://www.grammarcamp.com/enroll/admin/
      error: The service definition "adminTable" does not exist.
      trace: Exception InvalidArgumentException
sfServiceContainerBuilder->getServiceDefinition [ library/Am/Di.php : 436 ]
Am_Di->getServiceDefinition [ library/sf/sfServiceContainerBuilder.php : 80 ]
sfServiceContainerBuilder->getService [ library/Am/Di.php : 281 ]
Am_Di->getService [ library/sf/sfServiceContainer.php : 276 ]
sfServiceContainer->__get [ library/Am/Auth/Admin.php : 50 ]
Am_Auth_Admin->authenticate [ library/Am/Auth/Abstract.php : 137 ]
Am_Auth_Abstract->login [ library/Am/Controller/Auth.php : 79 ]
Am_Controller_Auth->doLogin [ library/Am/Controller/Auth.php : 54 ]
Am_Controller_Auth->indexAction [ library/Am/Controller.php : 139 ]
Am_Controller->_runAction [ library/Am/Controller.php : 116 ]
Am_Controller->dispatch [ library/Zend/Controller/Dispatcher/Standard.php : 295 ]
Zend_Controller_Dispatcher_Standard->dispatch [ library/Zend/Controller/Front.php : 954 ]
Zend_Controller_Front->dispatch [ library/Am/App.php : 1671 ]
Am_App->run [ index.php : 43 ]

aMember support suggested, I overwrite all the aMember files with new files they provided for my version. Which I did, and did not resolve the issue. I have also attempted to update aMember which was unsuccessful since I cannot run the DB update since I cannot login.

They have not been helpful.

I have confirmed all files have 644 permissions and folders 755.

We have not been able to access the backend for a couple of weeks now so any help would be greatly appreciated!

Cheers

Something similar happened to me yesterday, and the way I fixed it was to restore the sql database through the restore option. I'm using Amember 4.2.17 and I'm really glad I was able to access the restore option.

The problem itself started when I simply made a backup through the Backup utility. I'm a beginner so please take my comments with a grain of salt!