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4xx Level Errors

Get explanations for 400-level error messages.

This section provides information on how to interpret 4xx errors.

Pantheon 401 Unauthorized

This is the default response of an HTTP Basic Auth failure after a site administrator has locked the site's environment. This is usually not a platform failure as environment access can be set from the Dashboard Security tab.

In some circumstances, a 401 error can be triggered inadvertently if a site environment is locked, and a user passes the HTTP auth but the site sends a 401 HTTP status code.

You can resolve this error by disabling HTTP auth security for the environment in question.

Pantheon 403 Forbidden

Access denied to uploaded PHP files.

This message appears when you attempt to access a PHP file in Valhalla, Pantheon's network file system.

Pantheon also prevents public access via the web server to private files, .htaccess, and directory listings.

Pantheon 404 Unknown Site

The hostname ... is unknown. Please double-check that you have the right URL. If so, make sure it matches your Dashboard's custom domain settings.

This error typically is shown when there is an internal routing problem or a site environment does not exist.

Error 404 Not Found

Failed to load resource: the server responded with a status of 404 ().

This error or a similar error message displays when a web browser cannot find the element specified.

More specifically, this error occurs when the client (via web browser) successfully connects to the host (website’s application server), but is unable to find the actual resource requested (for example, a specific URL or file name). We recommend confirming that the URL or file name is correct and still exists on the site.

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