HTTP Status 404

HTTP status 404HTTP status 404 (Not Found) means the server is reachable but the requested URL does not exist. Individual 404 errors are normal; internal dead links are the real problem.Open glossary entry → (Not Found) means: the web server is reachable, but the requested URL does not exist. Typical causes are deleted pages, changed URLs, typos in links or a relaunch without a redirectA redirect forwards users and search engines from one URL to another. It can be permanent (301) or temporary (302) and transfers signals to the target URL.Open glossary entry → map.

Individual 404 errors are normal and do not automatically harm a website; the web changes and search engines expect pages to disappear. The real problems are:

• internal linksInternal linking refers to links that connect pages within the same website. They control how search engines and users find and thematically classify content.Open glossary entry → pointing to 404 URLs,
• 404 URLs in the XML sitemapAn XML sitemap is a machine-readable file listing a website's important URLs. It helps search engines discover content more efficiently but does not replace internal linking or guarantee indexing.Open glossary entry →,
• deleted pages with backlinks or former traffic.

The right action depends on the case: fix internal links directly, set a 301 redirectHTTP status 301 signals a permanent redirect: a URL has been permanently replaced by another. Search engines transfer the signals to the target URL.Open glossary entry → when a successor page exists, and keep 404 or 410 for permanently removed content. A good 404 page helps users, but must still technically send status code 404.