Answer¶

The following are the possible reasons that links are falsely flagged as broken or with errors:

• The target server was down at the time of the scan.

  A re-scan usually fixes the problem. If it does not fix the problem, ignore the link so that the system permanently stops checking this link, or mark the link as fixed if it is a temporary issue and you know that the link is not actually broken.

• The target server might be set to block site scanners and spiders such as Acquia Optimize.

• LinkedIn, Facebook, Twitter, and many other sites have a block on scanners such as Acquia Optimize, so that they can prevent themselves from the high amount of requests from the scanners during the scan. We scan thousands of websites every day and make many requests to these websites and they do often block our scanner. This can cause the scan to hang or stop. In most cases, you can safely ignore the link if you know that it is correct. The Acquia Optimize scan is configured to ignore these links automatically when they are reported to us.
  For more information and a list of known sites that block our scan, see the user guide article:
  Ignored links.

• The target server has an invalid HTTPS certificate.

  An invalid certificate causes the link to be marked as dead. Get in touch with the manager of the website and ask them to fix their certificate, or ignore the link if this is impossible.

• The link points to a login page.

  The link points to a page that requires a login. Such pages are often tagged as 'dead'. Ignore the link to stop checking this link permanently, or Mark as Fixed if it is a temporary (for example, in an unpublished state) known issue.