A new Exchange feature rolling out inside Office 365 allows meeting organizers to block people forwarding their meetings to all and sundry. The latest versions of OWA and Outlook 2016 click to run support the UI for the feature and blocks are built into Exchange Online and Exchange on-premises servers to stop blocked meetings sneaking through.
Hanging on to old email habits is a bad idea, especially if you use a cloud service like Office 365 where Microsoft introduces a steady stream of new features. The worst bad habit is password sharing. It’s time to stop this now.