Yahoo bounce message: 421 4.7.1 [TS03] Permanently deferred
This message indicates Yahoo! is seeing a high volume of emails from your IP address, which is a characteristic of unsolicited, bulk emailing.
- We do not recommend resending until you check your subscription practices and lists to ensure that messages are sent only to users who have requested it.
- If you are not the administrator of the mail server in question: please contact the administrator.
- If you are an administrator for message content or mailing policy and you have deployed significant changes or you have received this error for more than 48 hours, please review outgoing messages for objectionable content or practices.
Stop all this jibber jabber, what does it mean?
Yahoo believes that you are sending high volumes of spam to Yahoo users and is therefor temporary blocking any email that comes from your IP address
Did I do something wrong?
Most likely, yes. If you are certain you did not send any spam to Yahoo users, it is possible you have just received a new IP address from your Internet service provider
(ISP), that has been used for sending spam by some previous user.
How can I fix this?
Best would be to wait for a few hours before trying to send email again to Yahoo users. If you know you have been sending spam, simply stop sending spam to get rid of this block. This is a temporary problem though that will automatically get fixed over time, unless the spam problem does not get solved.