Why does the tool return "working" and "non-working" links? How can a link not work?
There's no perfect definition but here's another explanation :
working link :non working link :Code:Code:http://www.google.com
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I think a "non-working link" is the same as a "broken link"... that is, a link that takes you to a page that doesn't exist.
But it could also be literally a link that doesn't work, and doesn't take you anywhere, but then it isn't really a link, it is just an address (url)...
This is an interesting philosophical question!
If the link takes you to where it says it will, it works.
If the link does not take you to where it says it will, it does not work.
Links go dead all the time as sites are taken down (could be not renewing the domain to not having hosting anymore).
There is a software somewhere that will check your site(s) for any links that are no longer working.
But then, my take is if you have like 500 pages or more, useless work to hunt down those links and remove them.
So they get to live on forever.
There is probably an error to the code