What is the name of the domain?
YvonJanssen.nl
What is the error number?
550 S3150
What is the error message?
Rejected reason: upstream (hotmail-com.olc.protection.outlook.com.) error: failed to initalize: Unknown error: permanent error (550): 5.7.1 Unfortunately, messages from [104.30.8.87] weren’t sent. Please contact your Internet service provider since part of their network is on our block list (S3150). You can also refer your provider to Troubleshooting. [Name=Protocol Filter Agent][AGT=PFA][MxId=11BB18C8707837EB] [DS3PEPF000099E0.namprd04.prod.outlook.com 2025-05-09T19:42:11.115Z 08DD8C64
What is the issue you’re encountering
In cloudflare I’ve setup an email forward to an outlook.com address, but in the logging I can see errors suddenly. The error message means Outlook is blocking Cloudflare’s email forwarding server (IP 104.30.8.87) because it’s on a blocklist. Cloudflare needs to contact Microsoft to request removal from the blocklist.
What steps have you taken to resolve the issue?
Google for information, tried the support from cloudflare.
What are the steps to reproduce the issue?
Mail to [email protected]