404. That’s an error.
The requested URL /catalog/product_compare/add/product/2331/uenc/aHR0cDovL3d3dy5sZW9uc2FmZXR5cHJvZHVjdHMuY29tL3Rhc2VyLXB1bHNlLW55bG9uLWhvbHN0ZXIuaHRtbA,,/form_key/UaaH7XHEeGWUjJom/
was not found on this server. That’s all we know.