How to Remove System Attributes
By default, the system attributes cannot be removed from the Magento attributes management. They need to be removed manually. The easiest way to do this by editing specific rows in the Magento database.
Login to Magento admin pane and navigate to “Catalog>Attributes>Manage Attribute Sets”.
There you will find current product attributes.
Click on, for example, “Cell Phones” to explore its attributes. There you will find a list of attributes sorted by groups.
If you attempt to delete any selected group, an error will pop up, saying “this group contains system attributes”. Therefore, it cannot be removed as long as it contains system attributes.
To make an attribute non-system you will need to log in to the database and edit the records in the “eav_attribute” table. If you’re not sure what the database details are, check the “app/etc/local.xml” file, which stores the database name, username and password.
Once connected, click on the Magento database to view its tables. In the table list, find the one named “eav_attribute” and click it to see its rows. To find a specific attribute you should look at the “attribute_code” column.
To make the process faster, you can use search that is located in the top menu of phpMyAdmin. This way you will be able to search for an attribute’s name in the “attribute_code” column.
Finally, go back to Magento attribute manager and delete the attribute group whose attributes you have just set as non-system. You should now be allowed to delete them.
This is how you can customize Magento attributes to your requirements. All it takes is to edit a particular database table record in order to make the attribute non-system.