Can't send email to Outlook & Yahoo

Hi All,
I have set up the mail server well and everything works fine. I receive / send well from gmail.

but when i test to Outlook or Yahoo I got Undelivered Mail Returned to Sender![] said: 550 5.7.1

I have checked if the ip on any blacklist but it’s clean.

Is there anyone who has experienced this who can help?

note : All dns record is working fine SPF & DKIM & DMARC & PTR, and i used some postfix edit because some email was goes to spam using ipv6 to gmail.

smtp_address_preference = ipv4

Thanks for advance

You need to send request to outlook unblock your IP.

Thank you for reply

Unfortunately, I asked for it, and the response was as follows

Dear MHD

We have completed reviewing the IP(s) you submitted. The following table contains the results of our investigation.

Not qualified for mitigation
server ip
Our investigation has determined that the above IP(s) do not qualify for mitigation.

Please ensure your emails comply with the policies, practices and guidelines found here: Policies, Practices, and Guidelines.

To have Deliverability Support investigate further, please reply to this email with a detailed description of the problem you are having, including specific error messages, and an agent will contact you.

Regardless of the deliverability status, recommends that all senders join two free programs that provide visibility into the traffic on your sending IP(s), the sending IP reputation with and the user complaint rates.

Junk Email Reporting program (JMRP) When an user marks an email as “junk”, senders enrolled in this program get a copy of the mail forwarded to the email address of their choice. It allows senders to see which mails are being marked as junk and to identify mail traffic you did not intend to send. To join, please visit

Smart Network Data Services program (SNDS). This program allows you to monitor the ‘health’ and reputation of your registered IPs by providing data about traffic such as mail volume and complaint rates seen originating from your IPs. To register, please visit Smart Network Data Services.

There is no silver bullet to maintaining or improving good IP reputation, but these programs help you proactively manage your email eco-system to help better ensure deliverability to users.

Thank you, Deliverability Support

Can I do anything here?
Do I need order a new ip from the provider?

Just reply that mail and explain your mail usage and tell you just acquired that IP

1 Like

yeah! thank you. they unblock my ip server and they sent reply like this

My name is &****** and I work with the Deliverability Support Team.
We have implemented mitigation for your IP: ..**. and this process may take 24 - 48 hours to replicate completely throughout our system.

Sincerely, Deliverability Support.

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