SentToMemberOf shows every recipient type not distribution groups when you create transport rule in Exchange Server 2019 and 2016

Applies to: Exchange Server 2019Exchange Server 2016

Symptoms


When you create a transport rule (mail flow rule) and select the SentToMemberOf (is member of this group condition) parameter, it should show only the distribution groups, dynamic distribution groups, or mail-enabled security groups. However, the list shows everything including normal mailboxes, contacts, linked mailboxes, and every recipient type.

Cause


The filter that’s used in this scenario isn't correct.

Resolution


To fix this issue, install one of the following updates:

References


Learn about the terminology that Microsoft uses to describe software updates.