Note: Before you try to request removal, be sure to analyze your server to find out why you were listed in the first place. You have to fix the issue or they will just list your server again.
Do not try to get removed from the blacklist if you have not found the source of the problem.
If you are getting any error or bounce back message when you send email to the email address hosted with Office 365, then you can lookup your server IP address using the form at below link: