404. That’s an error.

The requested URL /catalog/product_compare/add/product/1697/uenc/aHR0cDovL3d3dy5sZW9uc2FmZXR5cHJvZHVjdHMuY29tL3BlcnNvbmFsLXNhZmV0eS9ibG93LWd1bnMtYW5kLWFjY2Vzc29yaWVzLmh0bWw,/form_key/JJfoQ7ChfJKkQqOR/ was not found on this server. That’s all we know.