What is a WINS Proxy Agent?

A. If you have non-WINS machines on your subnet and want them to be visible participants, you will want a Proxy Agent to be active within this subnet.
A WINS Proxy Agent is a WINS client that allows non-WINS clients to participate, by listening for broadcast name requests and then forwards them to a WINS server. It then returns the result to the requesting client.

Use a Registry Editor (e.g. regedt32.exe) to open HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NetBT\Parameters and set the EnableProxy parameter to 1.