Kurumsal mail adresimizden hotmail adresine mail atamıyoruz

Question

MErhaba ,

Kurumsal mail adresimizden hotmaile mail attığımız zaman aşağıdaki hatayı alıyoruz.

<<< 550 5.7.1 Unfortunately, messages from [213.14.87.66] 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=11BCB515EF03D211] [BN2PEPF000055DF.namprd21.prod.outlook.com 2026-02-03T03:54:43.917Z 08DE5A8B01F6C442]

Kontrol ettiğmizde Ip lerimiz microsoft tarafından https://sender.office.com dan kontrol ediyoruz kara listede görünmüyoruz.Hiçbir kara listede listelenmediğimiz halde hala hotmail,outlook adreslerine mail atamıyoruz.

Bu konuda Kurumuz ciddi sıkıntı yaşamakta acil olarak yardımlarınız rica ediyoruz.,

İyi çalışmalar dileriz

Answer 1

The error message you are encountering, 550 5.7.1 Unfortunately, messages from [213.14.87.66] weren't sent, indicates that your IP address has been blocked by the recipient's email service (in this case, Hotmail/Outlook). Even if you have checked your IP against the block list at the Microsoft delist portal and found no issues, it is possible that your IP is still being flagged due to previous spam activity or other reasons.

Here are some steps you can take to resolve this issue:

1. Check IP Reputation: Ensure that your IP address is not listed on any other blacklists. You can use various online tools to check your IP reputation.
2. Contact Your ISP: Since the error message suggests contacting your Internet Service Provider (ISP), it may be beneficial to reach out to them for assistance. They may be able to provide insights or help in resolving the issue.
3. Use the Delist Portal: If you believe your IP should not be blocked, you can use the Microsoft Anti-Spam IP Delist Portal to request removal from the blocked senders list.
4. Follow Best Practices: Ensure that your email practices comply with best practices to avoid being flagged as spam. This includes proper email authentication (SPF, DKIM, DMARC) and ensuring that your email content is not triggering spam filters.

If the issue persists, consider having the recipient contact Microsoft Support to investigate further as they may have more direct access to the reasons behind the block.

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References:

• External senders - Troubleshoot email sent to Microsoft 365
• Use the delist portal to remove yourself from the blocked senders list