Donna,
When you go look for the machine in RDC make sure you put the new port number you opened for that machines RDC connection into the computer search box; after it's IP address type (:port number) example: if the new RDC port is 1234 and machine address is 191.1.1.254 then to connect to that machine you would put
191.1.1.254:1234 into the computer box in RDC connection box
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