Admin Backend Broken

[steffen_leiss]

Hello,i got its error Message but i didnt solve it,please help

a:5:{i:0;s:64:"Mage registry key "_singleton/adminhtml/observer" already exists";i:1;s:1234:"
#0 /var/www/Website/shop/app/Mage.php(223): Mage::throwException('Mage registry k...')
#1 /var/www/Website/shop/app/Mage.php(477): Mage::register('_singleton/admi...', false)
#2 /var/www/Website/shop/includes/src/__default.php(26321): Mage::getSingleton('adminhtml/obser...')
#3 /var/www/Website/shop/app/Mage.php(448): Mage_Core_Model_App->dispatchEvent('adminhtml_contr...', Array)
#4 /var/www/Website/shop/includes/src/Mage_Adminhtml_Controller_Action.php(166): Mage::dispatchEvent('adminhtml_contr...', Array)
#5 /var/www/Website/shop/includes/src/__default.php(18361): Mage_Adminhtml_Controller_Action->preDispatch()
#6 /var/www/Website/shop/includes/src/__default.php(22864): Mage_Core_Controller_Varien_Action->dispatch('index')
#7 /var/www/Website/shop/includes/src/__default.php(22394): Mage_Core_Controller_Varien_Router_Standard->match(Object(Mage_Core_Controller_Request_Http))
#8 /var/www/Website/shop/includes/src/__default.php(25350): Mage_Core_Controller_Varien_Front->dispatch()
#9 /var/www/Website/shop/app/Mage.php(684): Mage_Core_Model_App->run(Array)
#10 /var/www/Website/shop/index.php(83): Mage::run('', 'store')
#11 {main}";s:3:"url";s:11:"/shop/admin";s:11:"script_name";s:15:"/shop/index.php";s:4:"skin";s:7:"default";}

[Damian Culotta]

Hi @steffen_leiss,

It seems you're using the Magento compiler. I guess you should avoid it and disable it.

The easier way is using Magento shell.

Go to the shell directory and then run:

php compiler.php state

Now you'll see the current status of or compiler. If is enabled and/or compiled, please, execute this commands:

php compiler.php disable
php compiler.php clear

Now is disabled and you've cleared all the generated files.

Can you try it and check if backend is failing again?

[gelanivishal]

Hello @steffen_leiss,

This error arriving due to empty values in registry.

to prevent it, you need to disable 'compilation' mode, and if you want to use it, re run it.

php -f shell/compiler.php disable
php -f shell/compiler.php clear
php -f shell/compiler.php compile

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