Response Codes: Internal Client Error (4XX)

Internal URLs with a client-side error.

This indicates a problem occurred with the URL request and can include responses such as 400 bad request, 403 Forbidden, 404 Page Not Found, 410 Removed, 429 Too Many Requests and more.

A 404 ‘Page Not Found’ is the most common, and often referred to as a broken link. This can occur to due an incorrect link, or a page that no longer exists.

How to Analyse in the SEO Spider

Use the ‘Response Codes’ tab and ‘Internal’ and ‘Client Error (4XX)’ filters to view these URLs.

View URLs that link to errors using the lower ‘Inlinks’ tab and export them in bulk via ‘Bulk Export > Response Codes > Internal > Client Error (4xx) Inlinks’.

Read our tutorial on ‘How To Find Broken Links‘.

What Triggers This Issue

This issue is triggered when an internal URL responds with a client-side error (4xx response code), such as a 404 ‘Page Not Found’.

For example:

HTTP/1.1 404 Not Found
Content-Type: text/html
Content-Length: 216


How To Fix

All links on a website should ideally resolve to 200 ‘OK’ URLs.

Errors such as a 404 Not Found or 410 Removed should be updated to their correct locations, removed and redirected to their new location where appropriate.

A 403 forbidden error is also common on the web today and occurs when a web server denies access to the SEO Spider’s request. This isn’t usually an issue for users if accessible in a browser and can often be resolved by switching the user-agent to Chrome via ‘Config > User-Agent’ and crawling again.

Please read our FAQs on how to approach each of the other following common responses:

• 400 Bad Request
• 403 Forbidden
• 406 Not Acceptable
• 429 Too Many Requests