Magento连接（到）系统备份（到）空白屏幕（到）固定权限（到）tmp in file.php（to）？

Question

PROBLEM: I used magento connect to add facebook (http://www.magentocommerce.com/magento-connect/facebook-connect-and-like-free.html) and backing up using the built in SYSTEM BACKUP, I received a blank screen on Frontend and when trying to access the admin panel.

Fixes I've Attempted: (1) magento-cleanup.php AND verified that all directories were 755 and all files 644 (2) after creating tmp directory ...Zend\file.php change => null to => tmp

RESULT: frontend is now up, but admin panel returns the following (I cannot access admin panel): There has been an error processing your request Exception printing is disabled by default for security reasons. Error log record number: 120xxxxxx3572

HERE IS THE ERROR LOG:

 a:5:{i:0;s:59:"Mage registry key "_singleton/belvgall/feed" already exists";i:1;s:1396:"#0 /home3/avintelc/public_html/rue50/app/Mage.php(223): Mage::throwException('Mage registry k...')
    #1 /home3/avintelc/public_html/rue50/app/Mage.php(477): Mage::register('_singleton/belv...', false)
    #2 /home3/avintelc/public_html/rue50/includes/src/__default.php(21667): Mage::getSingleton('belvgall/feed')
    #3 /home3/avintelc/public_html/rue50/app/Mage.php(448): Mage_Core_Model_App->dispatchEvent('controller_acti...', Array)
    #4 /home3/avintelc/public_html/rue50/includes/src/__default.php(14124): Mage::dispatchEvent('controller_acti...', Array)
    #5 /home3/avintelc/public_html/rue50/includes/src/Mage_Adminhtml_Controller_Action.php(160): Mage_Core_Controller_Varien_Action->preDispatch()
    #6 /home3/avintelc/public_html/rue50/includes/src/__default.php(14004): Mage_Adminhtml_Controller_Action->preDispatch()
    #7 /home3/avintelc/public_html/rue50/includes/src/__default.php(18399): Mage_Core_Controller_Varien_Action->dispatch('login')
    #8 /home3/avintelc/public_html/rue50/includes/src/__default.php(17933): Mage_Core_Controller_Varien_Router_Standard->match(Object(Mage_Core_Controller_Request_Http))
    #9 /home3/avintelc/public_html/rue50/includes/src/__default.php(20705): Mage_Core_Controller_Varien_Front->dispatch()
    #10 /home3/avintelc/public_html/rue50/app/Mage.php(684): Mage_Core_Model_App->run(Array)
    #11 /home3/avintelc/public_html/rue50/index.php(88): Mage::run('', 'store')
    #12 {main}";s:3:"url";s:16:"/index.php/admin";s:11:"script_name";s:10:"/index.php";s:4:"skin";s:5:"admin";}

website is rue50 (which is a subdomain of avintelc)

Answer 1

you should dis-activate the belvgall/feed extension and empty the var/cache/ directory . I think you will also have to empty the includes/src/ directory: I think it will be repopulated at the first load, but I am not sure, I never worked with the compiler (why do you? it is not really needed anymore)
here is a post that explain how to disable it through ssh, as you can't access the admin.