Cumulative Update 22 for Microsoft Exchange Server 2016 was released on September 28, 2021. It includes fixes for nonsecurity issues and all previously released fixes for security and non security issues. These fixes will also be included in later cumulative updates for Exchange Server 2016


Before You Begin

It’s important to go through release notes, prerequisites for newly available Cumulative Update. Evaluate your existing Exchange Server 2016 (with existing installed CUxx).

Preparing Active Directory

You need to prepare AD in the following manner in order to install CU22 successfully to avoid the following errors;

  1. Make sure you have installed .NET Framework 4.8
  2. Prepare AD Schema
  3. Prepare AD & Domain

Prepare Schema

Prepare AD

Putting Node into Maintenance Mode using EmmExDAGModule

To make things easier you can download the following PowerShell module to perform Exchange Server Nodes maintenance operations;


Extract the package files and import module;

Execute script with the following parameters;

Start-EMMDAGEnabled -ServerForMaintenance "Exchange server" -ReplacementServerFQDN "Exchange Server"

Wait until the process is not completed.

Finally ! Run Exchange Server 2016 CU22

Post Installation Tasks

Once Exchange Server 2016 CU22 is successfully installed now it’s time to bring back node from maintenance mode using the following command;

Stop-EMMDAGEnabled -ServerInMaintenance "Exchange Server"

Repeat same the other nodes and you are done !