We are currently aware that a large number of Microsoft 365 servers are being blocked by the SpamCop RBL - this is a reoccurance of the issue Microsoft were previously tracking as EX703958.
This may affect Shared Hosting customers ability to receive emails from Microsoft-hosted customers, and Microsoft 365 customers may experience issues with sending emails.
Microsoft is understood to still be working on this issue.
Update:
As there have been no updates from Microsoft, we have implemented a temporary workaround for this issue until Microsoft resolve their issues with SpamCop.
We will continue watching for any updates from Microsoft regarding the issue.
Update:
Microsoft have acknowledged the repeat issue as incident EX719348.
You can view the status from within your Microsoft tenancy, or by using this link:
https://admin.microsoft.com/Adminportal/Home?#/servicehealth/:/alerts/EX719348
If you're not logged in, you can view it publicly here:
https://west.jcteams.info/jcteamsinfo/docs/EX719348.html
We'll continue monitoring the status from Microsoft until the issue is resolved.
Update:
Microsoft has not yet fully resolved EX719348, and their latest update mentions isolating affected IP addresses which they are still doing.
This issue has also since been reported by technology news website The Register: https://www.theregister.com/2024/03/14/exchange_online_blocked_from_sending/
Update:
Microsoft have made some adjustments to help fix EX719348, they expect their changes to take effect over the following week.
We'll continue monitoring the status from Microsoft until the issue is resolved.
