Errorlytics, for example, is a software as a service (SaaS) application with a couple of added features that other 404 error tracking tools don't have, Jasra writes. The application collects information on all 404 errors that occur on the Web site, but also lets the user set up rules to handle the 404 error if it occurs again. It also generates a 301 redirect, sending the user to a working Web page.