Further to our announcement of 23 February 2026, email delivery to Microsoft addresses (@outlook.com, @hotmail.com, @live.com, @msn.com) has been fully restored.
What caused the problem
The problem was caused exclusively by Microsoft's filtering systems, as Microsoft was applying mass rate limiting (error code 451 4.7.650) to mail servers worldwide, affecting thousands of providers, organizations and businesses regardless of size and infrastructure. A similar case was an earlier Office 365 problem, which also concerned only Microsoft's servers.
Where things stand now
Your emails to recipients with Microsoft addresses are now delivered normally, without delays. Any emails that were waiting in the queue while the problem lasted have already been sent automatically by the mail server.
If you still have difficulty sending email to a specific Microsoft address, contact us and we will check the delivery flow. You can also see for yourself what happened to each message in cPanel Track Delivery.
Thank you for your understanding and your patience.
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