Smart Screen® email filters are influenced by a number of factors related to the sending IP, domain, authentication, list accuracy, complaint rates, content and more.Of these, one of the principal factors in driving down a sender's reputation and deliverability is their junk email complaint rate.
If you are an user looking for support with your account, please visit our end user support page.This change is part of Microsoft's overall Trustworthy Computing Initiative and was made to further reduce the risk of malicious HTML content reaching our users.One way to ensure that your messages aren't marked as being from an "unknown sender" is to join Return Path's Certification program, a third-party accreditation and reputation service that provides with a list of responsible senders.Microsoft does not allow this behavior and takes action on IPs that engage in it.If any of your sending IPs is blocked for namespace mining, please check that your machines or email sending accounts are not compromised by an attacker who may be using your servers to harvest email addresses, and ensure that any method you use to validate email addresses does not use namespace mining techniques.If that doesn't work, try connecting directly to the IPs.
If you are able to connect directly to the IP and not mail.hotmail.com, then it is likely there is an issue with your DNS server.
We may not accept email from senders who fail a reverse-DNS lookup.
In some cases legitimate senders advertise themselves incorrectly as a non-internet routable IP when attempting to open a connection to
These services have been tailored for senders and for ISPs.
To learn more about the Sender and ISP Services, go here.
Microsoft's Smart Screen® technology is designed to provide anti-spam filtering innovations for as well as other Microsoft products like Exchange Server, Microsoft Office Outlook and Windows Live Mail.