This is a bug in Magento 1.7.0.2 and has been identified as a bug as per http://www.magentocommerce.com/bug-tracking/issue?issue=14217.
An error occurred while saving this configuration: Notice: Trying to get property of non-object in /var/www/example.com/app/code/core/Mage/Adminhtml/Model/Config/Data.php on line 135
As a workaround, copy the file at app/code/core/Mage/Adminhtml/Model/Config/Data.php to app/code/local/Mage/Adminhtml/Model/Config/Data.php. If the app/code/local/* directory structure doesn't exist then you will need to create it.
Edit app/code/local/Mage/Adminhtml/Model/Config/Data.php at around line 135. Comment out the buggy code and replace with the workaround:
/** * Get field backend model */ //$backendClass = $fieldConfig->backend_model; //if (!$backendClass) { // $backendClass = 'core/config_data'; //} /** * Get field backend model */ unset( $backendClass ); // Add this line if (isset($fieldConfig->backend_model)) { $backendClass = $fieldConfig->backend_model; } if (!isset($backendClass)) { $backendClass = 'core/config_data'; }
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