Custom error pages and soft 404s TN-W19

Many sites configure a friendly 404 error page to be displayed instead of the web server’s default 404 page.

Problems occur if the custom error page returns a 200 OK HTTP status code instead of 404 Not Found, or redirects to an error page that returns 200 OK. Similar problems happen if missing pages cause a redirect to the home page.

• The 200 OK status indicates to the browser that the page was found, so the custom error page is cached. This is a problem if the missing page is restored - the cached custom error page will be returned until the cache expires.

• The 200 OK status means that Google cannot tell the difference between error pages and normal pages, and may either index your error pages, or reduce your site ranking.

• The 200 OK status means that link checking tools cannot detect broken links.

• A missing component file (JS/image/CSS) on a custom error page that returns 200 OK can result in an infinite loop, and denial-of-service on the web server. That happens because missing component on the error page causes a 404 which requests another copy of the error page, which triggers another 404 that requests another copy of the error page … and so on.

Note: You can see the HTTP status code returned in the Network tab of Chrome developer tools - click on the page in the list of resources to see the Status Code.

See also: Google help for soft 404s

Applies To: SortSite Desktop 1.0 or later

Last Reviewed: December 19, 2016