404. That’s an error.
The requested URL /catalog/product_compare/add/product/1104/uenc/aHR0cDovL3d3dy5lLWdyZWVudG91cmlzbS5jb20vY29hY2gtdGFza2VyLXRvdGVzLWtyaXN0aW4uaHRtbA,,/form_key/4ydwOkVtcaqNcOUj/
was not found on this server. That’s all we know.