If you’re having trouble sending emails to any of the following outlook’s domain names:
hotmail.com
live.com
msn.com
outlook.com
Then it’s most likely that your IP has been blacklisted by Microsoft, and you will need to get it delisted before your emails can reach any outlook users.

Before you begin, be sure to investigate the reason why your IP (or IPs) got blacklisted in the first place, and make sure to fix the issue, before asking for whitelisting/delisting on their site. This step is extremely important, and if you do not fix the issue that got you blacklisted, you’ll just end up being blacklisted again shortly after getting whitelisted.

In order to ask outlook for delisting your IP address, you’ll first need to access this link:
https://support.live.com/eform.aspx?productKey=edfsmsbl3&ct=eformts&scrx=1

Carefully read and submit the form located at the link above.

It may take the outlook delivery support team a while to get back to you with an answer on your request, so it’s very important to be patient.

 

Please note that outlook uses their own private blacklists, which nobody outside of their organization can access or query or run blacklist checks on. This basically means that HetrixTools cannot monitor or blacklist check the outlook blacklists for you.