Symptoms
An Edge Transport server stops responding because of a deadlock in the Shadow Redundancy Manager in Microsoft Exchange Server 2019 or Exchange Server 2016.
Resolution
To fix this issue, install one of the following updates:
For Exchange Server 2019, install the Cumulative Update 6 for Exchange Server 2019 or a later cumulative update for Exchange Server 2019.
For Exchange Server 2016, install the Cumulative Update 17 for Exchange Server 2016 or a later cumulative update for Exchange Server 2016.
References
Learn about the terminology that Microsoft uses to describe software updates.