Traffic control settings.
Link Whisper can get a lot of false positives when your site has many links to an external site, and the external site has traffic control systems active. You see, Link Whisper is capable of checking many links very quickly. And sometimes when a site sees dozens or hundreds of page requests in less than a minute all coming from the same source, it thinks it’s under attack. The way they usually handle this is by telling Link Whisper the page doesn’t exist (404 error), or that it doesn’t have permission to access that page (403 error). Sites may use different error codes, but these are the common ones.
Link Whisper does have a way of coping with this situation. After the broken link scan is completed, Link Whisper will slowly re-check all of the broken links that it’s found. It checks one link every ten minutes, so it’s very unlikely that the traffic control systems will be engaged. If on the re-check the link is found to be good, it’s removed from the Error Report.
Robot control settings.
Another cause of false positives is that the site thinks the link check request from Link Whisper is coming from a robot. Some sites try to avoid responding to automated requests because they’re not real visitors and may be part of an attack. So sometimes they identify Link Whisper’s requests as coming from a robot.
Fairly often, sites just won’t respond to the request (28 error), will say it’s not available (503 error), or will respond that the page is unavailable (403 error). If the link is to a page on LinkedIn.com, the response will be a “999 Access Denied” error.
Since the site is identifying Link Whisper’s requests as coming from an automated source, the delayed re-checking won’t clear them. You can either ignore the link by clicking the “Ignore” button or contact support to let us know about the issue.
Site related causes.
You may see false positives if Link Whisper can’t process the links on your site. You may also see false positives if your site’s software doesn’t support Link Whisper. In both cases, you will see many links with a “925” error. This error means that Link Whisper isn’t able to scan the link. Usually, the link can’t be scanned because it has a format error. You can test this by going to the page the link is on, and clicking the link. If your browser is not able to follow the link, then there’s a problem with the link format. If your browser can follow the link, then it’s possible your site doesn’t support the software needed to scan links.
