HTTP 404 error

  • Fabian Sinner
  • January 24, 2024

Table of content

    HTTP 404 error

    One of the most common errors encountered on the Internet is the HTTP 404 error code. It indicates that the desired page or requested file is no longer available. If you make a request in your browser for the desired destination, but it is not available, the server displays a 404 error code.

    In most cases, you will then receive a generic display of black text on a white background showing you a message such as “404 Not Found” or “404 – Page not found”.

    404 errors happen quickly: In many cases, this applies to old embedded links that have lost functionality over the years because the linked page no longer exists or the target source has changed. Google informs webmasters at regular intervals when such errors occur. It is important to react quickly because a 404 error can have a negative impact on your SEO ranking.

    How does a HTTP 404 error occur?

    A 404 error code happens faster than you think. This is primarily why it’s the most common error code on the Internet – a 404 error can occur without the host even realizing. Some of the many causes include:

    • The website no longer exists
    • The web server cannot be reached
    • The URL of the resource has been renamed and the target link has changed as a result
    • The resource has changed location and has been moved elsewhere
    • The user has entered an incorrect URL in the browser

    Even if all of the points mentioned can lead to a 404 error, the usual reason is the renaming or relocation of an existing URL. If a clean 301 redirect is not used, the page is suddenly no longer accessible via the previous link – and the 404 error code is displayed.

    A classic use case here is the revision of the existing link structure. If a webpage is transferred to a different link cluster, e.g., by moving an existing product to a different category, the entire structure of the URL often changes.

    Another example would be renaming a page because the product name has changed, for example. Some content management systems (CMS) then have the habit of automatically adapting the link to the new name. The result: the link changes and the old address is no longer accessible without redirection.

    What are the disadvantages of 404 errors for a website?

    One or two overlooked HTTP 404 error messages do not pose an immediate risk to a website, although they should still be corrected. A more pressing issue is a large number of inaccessible pages, which can be broken down into two potential risk factors: The user experience and search engine optimization.

    User experience

    A user who receives a large number of error messages on a website will not have a good surfing experience and will most likely leave the site quickly. Users expect to find everything as quickly and reliably as possible. If this requirement is not met, their satisfaction suffers. The bounce rate increases and with it the success of the company.

    In addition, there is little chance that users who have left the site will ever visit it again. Importantly, too, factors such as bounce rate and time spent on a page can impact a website’s SEO ranking.

    Search engine optimization

    Google’s crawler regularly visits websites and checks them for either valuable content or potential problems. Valuable and reliable content is rated as extremely positive – broken or untraceable websites achieve the opposite. If the crawler discovers a large number of 404 errors or other error codes, this will inevitably lead to a downgrading of the website at some point and thus to a negative result in the organic Google rankings.

    How do I identify a HTTP 404 error on my website?

    The more extensive your website is, the more complex the search for 404 errors can become. Checking all pages manually will only be a sensible solution for very few websites. Therefore, there is no way around special tools that do the work automatically and reliably. The following two options are frequently used:

    • Google Search Console: The classic among webmaster tools. The Google Search Console is free to use and quick to set up. The tool sends regular updates to the registered user if discrepancies are discovered.
    • Dead Link Checker: This free tool is popular with many webmasters because the check can be triggered manually and there is also the option of defined auto-checks.

    There are other link check options on the market that can be used either for free or for a fee. In the end, they all work more or less the same and do the work for the website owner. They detect problems such as the 404 error code.

    How can a HTTP 404 error be fixed correctly?

    During the lifetime of a website, it is almost impossible to prevent 404 errors from appearing in certain places. It is important that these are recognized by a tool in order to fix the problem promptly. Some solutions for resolving the problem include:

    Set redirects

    As stated above, 404 errors are often caused by a name change or by modifying the actual link. If this is the case, a 301 redirect should be set directly, which forwards from the original link to the new address. If you delete an existing website completely, it is also worth redirecting to a related page that may also be of interest to the visitor. Such a redirect can be set at any time, even retrospectively.

    A 301 redirect can be carried out either via your own .htaccess file or via the internal content management system (CMS). Please note that a 301 redirect is permanent and remains in place until it is removed by the webmaster.

    Do not set a redirect

    Although a permanent 301 redirect usually makes sense, there will always be situations in which webmasters deliberately want a HTTP 404 error. This is usually the case for deleted pages that cannot be redirected to related pages.

    While this procedure is rather unusual on websites with text content (e.g., blog or glossary), it can be particularly useful for e-commerce stores. For example, if the product is no longer available – an automatic redirect to another product is more likely to cause confusion than be helpful for the customer.

    It is important to know that desired 404 pages should be specially designed. They should be visually embedded in the existing website and thus signal that the 404 error is actually intended. If the user is shown a generic white error page, this looks more like an unwanted error than a conscious decision.

    Do not forget: Internal linking

    If the address of a website is permanently changed or even deleted, it is worth thinking about internal linking. Which pages link to the page that no longer exists? Where should you proactively make improvements?

    It is unpleasant for the user to be directed to a 404 page via an internal link – even if the webmaster deliberately displays the error code. The best course of action is to adjust the internal linking proactively so as not to frustrate the user. If you have overlooked a few links, the link monitoring tool you are using will inform you sooner or later.

    How you deal with a HTTP 404 error therefore depends entirely on the needs of the website operator. The important thing is to identify the errors quickly and react accordingly. Thanks to various tools and possible solutions, however, such problems are not a critical stumbling block, provided they are dealt with conscientiously.

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