unable to add yahoo/google mail accounts

Disabling Avast mail shields worked for me.

It is the same for me here. Thank you very much.

What if all of my Verisign certificates are already trusted?

I had to delete the ~/Library/Keychains/ directory (and everything in it) and reboot to get it working again.

I use Sophos for antivirus. All the Verisign certificates were within their defined dates, and you can no longer delete expired root certificates.

I don't use Keychain so it was a bit of a surprise that deleting the directory solved the problem.

Brilliant, thanks for the fix!

Thanks, this is the only reply that worked for me, i've had the problem for weeks and this instantly sorted it. I'm really greatfull for your post!

Similarly I turned off Avast, made the changes, verified access and enabled Avast right after it... no issues after that...

Thanks.

Disabling AdGuard fixed mine too! Thanks!

Helpful

Avast now has, in its Mail Shield settings, a place where you can exclude the "google.com" server.

this worked for me thanks

YES! thank you! I disabled my shield on AVAST just to add the gmail account back and viola - it worked. Thank you! GZNYC

Thanks This was my issue. Disabled the Mail protection and it worked fine!