After a week of time wasted trying to get any sensible comment from the helpdesk (yes, I know that they are snowed-under with password changes) I thought I would see if anyone has any thoughts on this error I'm getting.
I have a talk21.com account which I access using POP and SMTP from Google. This has worked well for the past 5+ years. That was up until the beginning of October 2016 since when I have been getting error "Error 421 : Too Many Messages" while sending. Receiving email is working fine.
My account is on Yahoo mail, yes I have changed my password in september, but it was working well after that point. Email sending from the BT-Yahoo email cllient works.
SMTP Connection details being used
Mail Server: mail.btinternet.com Port: 465
Messages are queued and after 24 hours I get the first 421 warning message, Google retries over 3 days before I get a permanent failure message.
No, I don't send many emails - perhaps a dozen a day. AV is up-to-date and no reports of attacks or unexpected logins.
Does anyone have any thoughts or tests to try??
In the meantime I'll continue to try to speak to someone on the helpdesk that knows about SMTP/POP and does not just say "it is a client problem" just because the web client works.
Cut-paste of exact message ...
Technical details of temporary failure: Google tried to deliver your message, but it was rejected by the relay mail.btinternet.com [126.96.36.199].
The error that the other server returned was: 421 Too many messages (188.8.131.52) from 184.108.40.206