Missing files

What we check

We load the home page in a real browser and look at what the server answers for every requested file. A request counts as failed with a status code of 400 or above (such as 404 "not found" or 500 "server error") or with a network error, because the address cannot be resolved or the server is unreachable.

• Files of the site's own domain: warning if scripts, stylesheets, fonts or embedded pages are missing, or if three or more files are missing. Note for individual images or other files.
• Files from third parties: note.

Requests the browser cancels itself, say because the page navigates on, do not count.

Why it matters

A page consists of dozens of files. If one is missing, the browser notices silently: a missing stylesheet leaves the page unformatted, a missing script leaves the menu stuck, a missing font is replaced by a fallback, a missing image shows an empty area. Each of these gaps costs trust, and none produces an error message for the operator.

Missing files typically appear when moving to a new server, when switching the theme, when deleting a plugin whose files are still embedded, or because an image a page still uses was deleted from the media library. Every failed request also costs loading time, because the browser waits for the answer.

Search engines and audit tools rate many 404 answers as a sign of missing maintenance.

How to fix it

The detail in the report names the status code and the address of every failed file.

• 404 for own files: the file was moved, deleted or never uploaded. Upload it to the address named, correct the path in the template, or remove the embed.
• 403: the server refuses access. Check file permissions and rules in .htaccess or the server configuration.
• 500 or 503: the server has a problem with this address, often a script that generates the file dynamically. The server's log files show the cause.
• Network error: the domain no longer exists or does not answer, typical for switched-off services. Remove the embed.
• Leftovers of old plugins or themes: search the HTML for the path and remove the reference in the CMS.

How to check it yourself

Open the developer tools (F12), tab "Network", and reload the page. Lines marked red are failed requests; the "Status" column shows the answer. The "Errors" filter or sorting by status finds them quickly.