404. That’s an error.

The requested URL /catalog/product_compare/add/product/102/uenc/aHR0cDovL2NsZWFudHVuaW5nLmNvbS8yLWhpZ2gtcG93ZXItMnctczI1LTExNTYtYmF5MTVkLWJhc2UtbGVkLWJ1bGJzLXN1cGVyLWJyaWdodC1zMjUteTE1ZC0yd2hwLmh0bWw,/ was not found on this server. That’s all we know.