Hop 404 Reporter

Hop 404 Reporter will log and alert you to 404 (page not found) errors happening on your website, which will help your site look good to the search engines and satisfy your site visitors.

This should be a default install for most EE projects.

This ExpressionEngine add-on logs each time a website visitor encounters a 404 error page. It records what URL the website visitor came from, and what page they were trying to get to. As well as creating a log, the module allows you to set up email notifications of 404 errors, grouped and filtered in ways that make sense to you.

Using the information in Hop 404 Reporter’s logs, you can find and correct broken links on your own website, notify other websites about broken links to your content, and generally deliver a higher quality and more professional website.