Microsoft strengthens email security measures
Microsoft is introducing a new Exchange Online security feature that will automatically start throttling and eventually block all emails sent from "persistently vulnerable Exchange servers" 90 days after the admins are pinged to secure them. The new system's primary goal is to help Exchange admins identify unpatched or unsupported on-prem Exchange servers, allowing them to upgrade or patch them before they become security risks. This new enforcement system will only affect servers running Exchange Server 2007 using OnPremises connectors to send mail to allow fine-tuning before expanding to all Exchange versions, regardless of how they connect to Exchange Online, after tuning.