Emails to Outlook and Hotmail addresses being rejected
I am finding that emails being sent via Thunderbird to Hotmail and Outlook email addresses are being rejected. How can I overcome this?
تمام جوابات (3)
Please post screenshot of the complete error message and maybe someone can give suggestions.
Similar message when sent to a Hotmail address
"This message was created automatically by mail delivery software. A message that you sent has not yet been delivered to one or more of its recipients after more than 24 hours on the queue on queue02c.mail.zen.net.uk.
The message identifier is: 1w56qu-0000000Eay9-30yw The date of the message is: Tue, 24 Mar 2026 18:51:41 +0000 The subject of the message is: Re: Friday's peal attempt
The address to which the message has not yet been delivered is:
margaret.sherwood@outlook.com host outlook-com.olc.protection.outlook.com [52.101.11.6] Delay reason: SMTP error from remote mail server after pipelined sending data block: 451 4.7.650 The mail server [212.23.3.242] has been temporarily rate limited due to IP reputation. For e-mail delivery information, see https://aka.ms/postmaster (S775) [Name=Protocol Filter Agent][AGT=PFA][MxId=11BD1421BC3F4AED] [SA2PEPF00001507.namprd0[truncated]
No action is required on your part. Delivery attempts will continue for some time, and this warning may be repeated at intervals if the message remains undelivered. Eventually the mail delivery software will give up, and when that happens, the message will be returned to you."
This URL from Microsoft explains the issue: https://www.suped.com/knowledge/email-deliverability/sender-reputation/what-causes-temporary-rate-limiting-due-to-ip-reputation-with-microsoft-email-servers This is not a thunderbird issue, but an IP issue.