3  3SharesUPDATE: [11/20/2018] I had an error in the transport rule configuration in the last example, as well as a note that a TR would NDR external traffic.  I have this post accordingly. We’re all familiar with how Office 365 tenants work–when you spin up a new Office 365 tenant, you get a managed domain (tenant.onmicrosoft.com).  … Continue reading Block direct delivery to @onmicrosoft.com addresses in a hybrid environment