@Moshe Raab, PhD
MSMQ is available as a component of Windows 2000 and later. Because Message Queuing is a component of Windows, its use is covered by the Windows license. If you have a valid license to use Windows, then you can use MSMQ.
Installing Message Queuing services (MSMQ) on Windows Server 2016 or later
Microsoft Message Queuing (MSMQ) stores emails temporally, while they are scanned or waiting to be actioned by the mail server.
To install MSMQ on Windows Server 2016 or later:
Start Server Manager.
Go to Manage > Add Roles and Features.
In the Before You Begin screen, click Next.
Select Role-based or feature-based installation and click Next.
Select the server where to install the feature.
Go to Features, and navigate to Message Queuing > Message Queuing Services and select Message Queuing Server.
Click Install to start the installation.
The setup may require a system restart. Click OK to finish.
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