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You will need to configure the local Windows firewall and network firewall to allow connections to these ports.
Windows Firewall Configuration
From the Server Manager window select "Tools | Windows Firewall with Advanced Security";
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Public - Traffic to and from non-local sources such as the World Wide Web.
Adding Firewall Rules for the Inbound Ports
The default RADIUS server listens on ports 1812 (UDP), 1813 (UDP) and 8090 (TCP), these ports need to be opened for inbound traffic.
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