404. That’s an error.

The requested URL /catalog/product_compare/add/product/2492/uenc/aHR0cDovL3d3dy5sZW9uc2FmZXR5cHJvZHVjdHMuY29tLzEyODBwLWhkLWZpc2gtZXllLTMtMC1tcC1jYW1lcmEtd2l0aC13aS1maS1hbmQtZHZyLmh0bWw,/form_key/8WD99EyPGCxGIBIb/ was not found on this server. That’s all we know.