Error code when sending: Cannot send message due to possible abuse

[alecst]

I've had this same problem.

What you need to do is log into yahoo mail via the webpage, and change  your password. This is most important, Many many Yahoo emails have been hacked,  if you do a search, you'll see what I mean. Don't forget to change your password in Thunderbird after you've changed it on the web, then you'll be fine.

[alecst]

I've had this same problem.

What you need to do is log into yahoo mail via the webpage, and change  your password. This is most important, Many many Yahoo emails have been hacked,  if you do a search, you'll see what I mean. Don't forget to change your password in Thunderbird after you've changed it on the web, then you'll be fine.

[Sigh]

Excellent - this worked; and I was able to remove the Reply-To field in the Thunderbird account settings.

Thank you!

[Hywel]

Thanks all.  Removing the reply-to field makes it work OK on HTML via Thunderbird