The specified AMP Page URL includes a canonical link element that points to a resource returning a Forbidden (403) HTTP status code.
Why is this important?
Canonical links on AMP HTML pages should reference the equivalent non-AMP page, or the AMP page itself if no equivalent exists. If this link leads to a resource that is forbidden, then search engines might not be able to access the non-AMP page, impacting the visibility of the AMP page in search results.
The presence of a correct canonical link is critical for an AMP page's validity. An inaccessible canonical URL confuses search engines, lowering the likelihood that the AMP page will appear in search results.
What does the Optimization check?
The check is triggered when an AMP Page URL's canonical tag points to a resource that is inaccessible because it returns a 403 (Forbidden) status when the page is crawled.
Examples that trigger this Optimization
Imagine the AMP Page URL: https://example.com/amp/page-a/
This URL would trigger the Optimization if it contained a canonical link as shown below, and that URL was inaccessible:
<!doctype html><html amp> <head> <meta charset="utf-8"> <title>Sample document</title> <link rel="canonical" href="https://example.com/pages/page-a/" /> ... </head> ...</html>
This would be the case if the canonical URL returned the following header response:
HTTP/... 403 Forbidden...
How do you resolve this issue?
This is marked 'Critical' as it could significantly impact your site's search performance. Addressing Critical issues should be of the highest priority.
If the canonical points correctly, investigate the cause of the 403 status to resolve the issue. Be aware, however, that protection systems might trigger false alarms for elevated traffic or crawling patterns, resulting in 403 statuses meant for DDoS protection.
Should the page be mistakenly removed or deleted, republish it promptly, ensuring it responds with a 200 status code.
If the canonical is incorrect, adjust it on the AMP page to point to the appropriate non-AMP version, which itself should have a self-referencing canonical link. An example of correct implementation is as follows:
The non-AMP page should define a self-referential canonical tag as well as noting its AMP counterpart:
Then ensure that the AMP page's canonical tag correctly references the non-AMP page:
<link rel="canonical" href="https://example.com/pages/page-a/" />