我已经从magento安装了扩展，从网站连接并注销，但当我试图访问管理面板时，现在我遇到了错误。
"处理您的请求时出错出于安全原因，默认情况下禁用异常打印。错误日志记录编号：1303816771146"
当我在var/report下跟踪错误文件时，我发现了以下错误报告。
"a:5:{i:0;s:71:"Mage registry key "_singleton/emailattachments/observer" already exists";i:1;s:2604:"
#0 /home/globaltrimming12/public_html/app/Mage.php(223): Mage::throwException('Mage registry k...')
#1 /home/globaltrimming12/public_html/app/Mage.php(477): Mage::register('_singleton/emai...', false)
#2 /home/globaltrimming12/public_html/includes/src/__default.php(21770): Mage::getSingleton('emailattachment...')
#3 /home/globaltrimming12/public_html/app/Mage.php(448): Mage_Core_Model_App->dispatchEvent('core_block_abst...', Array)
#4 /home/globaltrimming12/public_html/includes/src/__default.php(1988): Mage::dispatchEvent('core_block_abst...', Array)
#5 /home/globaltrimming12/public_html/includes/src/__default.php(28179): Mage_Core_Block_Abstract->setLayout(Object(Codnitive_Extifcon_Model_Core_Layout))
#6 /home/globaltrimming12/public_html/includes/src/__default.php(28195): Mage_Core_Model_Layout->createBlock('adminhtml/page_...', 'head')
#7 /home/globaltrimming12/public_html/includes/src/__default.php(27962): Mage_Core_Model_Layout->addBlock('adminhtml/page_...', 'head')
#8 /home/globaltrimming12/public_html/includes/src/__default.php(27928): Mage_Core_Model_Layout->_generateBlock(Object(Mage_Core_Model_Layout_Element), Object(Mage_Core_Model_Layout_Element))
#9 /home/globaltrimming12/public_html/includes/src/__default.php(27929): Mage_Core_Model_Layout->generateBlocks(Object(Mage_Core_Model_Layout_Element))
#10 /home/globaltrimming12/public_html/includes/src/__default.php(14024): Mage_Core_Model_Layout->generateBlocks()
#11 /home/globaltrimming12/public_html/includes/src/__default.php(13949): Mage_Core_Controller_Varien_Action->generateLayoutBlocks()
#12 /home/globaltrimming12/public_html/includes/src/Mage_Adminhtml_Controller_Action.php(275): Mage_Core_Controller_Varien_Action->loadLayout(NULL, true, true)
#13 /home/globaltrimming12/public_html/app/code/core/Mage/Adminhtml/controllers/IndexController.php(81): Mage_Adminhtml_Controller_Action->loadLayout()
#14 /home/globaltrimming12/public_html/includes/src/__default.php(14098): Mage_Adminhtml_IndexController->loginAction()
#15 /home/globaltrimming12/public_html/includes/src/__default.php(18482): Mage_Core_Controller_Varien_Action->dispatch('login')
#16 /home/globaltrimming12/public_html/includes/src/__default.php(18016): Mage_Core_Controller_Varien_Router_Standard->match(Object(Mage_Core_Controller_Request_Http))
#17 /home/globaltrimming12/public_html/includes/src/__default.php(20808): Mage_Core_Controller_Varien_Front->dispatch()
#18 /home/globaltrimming12/public_html/app/Mage.php(684): Mage_Core_Model_App->run(Array)
#19 /home/globaltrimming12/public_html/index.php(87): Mage::run('', 'store')
#20 {main}";s:3:"url";s:7:"/admin/";s:11:"script_name";s:10:"/index.php";s:4:"skin";s:5:"admin";}"
请让我知道在哪里做更改，这样我就可以登录到管理面板。
看起来，你的magento编译是打开的。在安装扩展之前，一定要关闭编译，当然还要禁用缓存。在此处查找有关编译的更多信息。