Some customer complained that his mail he sent via my hosting webmail and via smtp was not delivered to his hotmail mailbox.

Error message he got was:

This message was created automatically by mail delivery software.
A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed:

[email protected]
SMTP error from remote mail server after MAIL FROM:<[email protected]> SIZE=1704:
host []: 550 SC-001 (BAY0-MC6-F36) Unfortunately, messages from myhostingserveriphere weren't sent. Please contact your Internet service provider since part of their network is on our block list. You can also refer your provider to

------ This is a copy of the message, including all the headers. ------

Return-path: <[email protected]>
Received: from localhost.localdomain ([]:46415
by with esmtpa (Exim 4.82)
(envelope-from <[email protected]>)
id 1WpN1e-0008KD-Jf
for [email protected]; Tue, 27 May 2014 15:27:13 -0400
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
Date: Tue, 27 May 2014 15:27:03 -0400
From: [email protected]
To: [email protected]
Subject: test
Message-ID: <[email protected] o>
X-Sender: [email protected]
User-Agent: Roundcube Webmail/0.9.5

Importnt part is in bold text. What it mean? This mail was sent from Hotmail mail server back to client saying his mail he sent to hotmail was not delivered and it was rejected because the IP from which he sent mail is on Hotmail blocklist. So its fault of the webhosting provider. When examining mail history, it was found that there was more rejected emails from Hotmail and these was looking spammy, so i tweaked script that sent spammy emails to look less spammy, then contacted Microsoft (Hotmail, Outlook owner) following way..

by submitting this form:;ct=eformts
(5 minutes to complete)

This email i received within 1 hour!! after submitted

Dear *

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

Conditionally mitigated
Our investigation has determined that the above IP(s) qualify for conditional mitigation. These IP(s) have been unblocked, but may be subject to low daily email limits until they have established a good reputation.

Please note that mitigating this issue does not guarantee that your email will be delivered to a user’s inbox.

Ongoing complaints from users will result in removal of the mitigation.

Mitigation may take 24 - 48 hours to replicate completely throughout our system.

If you feel your issue is not yet resolved, please reply to this email and one of our support team members will contact you for further investigation.

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;page=support_home_ options_form_byemail&amp;ct=eformts.

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

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
So it means it was quick process

One can then monitor mail data send from his server IP to Hotmail by Microsot tool: