CloudFlare Email routing at outlook.com blocklist and rate limited because of IP reputation
Email routing from outlook.com to CloudFlare Routing CatchAll to outlook.com:
Error 1:
Rejected reason:
upstream (outlook-com.olc.protection.outlook.com.) error: failed to initalize: Permanent Unknown error: permanent error (550): 5.7.1 Unfortunately, messages from [104.30.10.209] 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 http://mail.live.com/mail/troubleshooting.aspx#errors. [Name=Protocol Filter Agent][AGT=PFA][MxId=11BC4895305A76C2] [MN1PEPF0000ECD6.namprd02.prod.outlook.com 2025-11-18T18:27:44.9
Error 2:
Rejected reason:
upstream (outlook-com.olc.protection.outlook.com.) temporary error: Unknown error: transient error (451): 4.7.650 The mail server [104.30.8.58] 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=11BC48E964DE9B87] [SJ1PEPF0000231B.namprd03.prod.outlook.com 2025-11-18T18:10:17.935Z 08DE2474B50C5E37]
Error 1:
Rejected reason:
upstream (outlook-com.olc.protection.outlook.com.) error: failed to initalize: Permanent Unknown error: permanent error (550): 5.7.1 Unfortunately, messages from [104.30.10.209] 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 http://mail.live.com/mail/troubleshooting.aspx#errors. [Name=Protocol Filter Agent][AGT=PFA][MxId=11BC4895305A76C2] [MN1PEPF0000ECD6.namprd02.prod.outlook.com 2025-11-18T18:27:44.9
Error 2:
Rejected reason:
upstream (outlook-com.olc.protection.outlook.com.) temporary error: Unknown error: transient error (451): 4.7.650 The mail server [104.30.8.58] 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=11BC48E964DE9B87] [SJ1PEPF0000231B.namprd03.prod.outlook.com 2025-11-18T18:10:17.935Z 08DE2474B50C5E37]
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