I've just come up on something....

In an attempt three days ago to be more transparent (it's a news site), we added "send me an email" links to each author's bio as well as links to the Company and the Agency in the footer.

Except these links weren't inserted correctly in the footer, and half the authors didn't get the right links either.

So instead of it being a "mailto" link, it was just the email which when you hovered over was the url of the page with the author email at the end... the same thing that's happening in the errors.

Same for the footer links. They weren't done correctly and sending users to OURSITE.com/AGENCY1 instead of AGENCY1's website. I've made the changes and put in the correct links. I have asked for a recrawl to see if that changes anything.

Just wanted to update quickly. The mistakes in the email links as well as the links to the two company sites proved to be the problem. After recrawling the sites, the 7,000+ errors are gone.

It's interesting because I was about to get very upset with Moz, thinking their bot had caused me half a day of headaches for nothing. Turned out they picked up an error before any other system did that would likely have done a lot of damage given that they were all contact links meant to improve transparency.

Hopefully, we caught and fixed the problem in time. In any case, thanks for your help effectdigital.