When I click "Restart PHP" in Zend Server web interface, I get this error in the logs: PHP Warning: Cannot restart PHP: permission denied for user IIS APPPOOL\DefaultAppPool. in C:\Program Files (x86)\Zend\ZendServer\GUI\application\CE\models\ZwasComponents\Util\Api\UserServer.php on line 86 Based on http://kb.zend.com/index.php?View=entry&EntryID=426 I tried to give permissions to user IIS APPPOOL\DefaultAppPool to the folder C:\Program Files (x86)\Zend\ZendServer\, however it still gives the same error. Do you know to what resources the application pool does not have permissions to?