This site provides information to information technology professionals who administer systems that send email to and receive email from Outlook. It also provides some information about how users with Outlook accounts can report junk email and phishing attempts. However, it is not intended to provide extensive support to Outlook users. If you are an Outlook user in need of support, please visit Windows Live Support.

To navigate this site please use the navigation links to the left, or to jump right to the most requested information please click on one of the links below.

• I am an Outlook user in need of support.
• Email I send is being blocked or junked by Outlook.
• I want information about SMTP error codes returned by Outlook servers.

New Postmaster Site

Welcome to the new Outlook Postmaster site. We’ve introduced this new site in order to help senders improve their reputations and increase deliverability into Outlook inboxes.