Catchable fatal error: Object of class WP_Error could not be converted to string in …./wp-content/plugins/wp-e-commerce/wpsc-includes/category.functions.php on line 361 How I solved this error and it might save you some time. I converted over an OsCommercer store to WP-Ecommerce using cart to cart a great way to bring over that database especially when huge like this one was. It had over 6k items and more. The conversion tests all went well so I went ahead with full conversion.  That’s when the site broke after full conversion; suddenly I was getting the following error Catchable fatal error: Object of class WP_Error