Hello, I was trying Grpc and I made a Service that is working. Then I made a Console App as client and it works Ok. Then a Winforms App that work too. When I made a WPF App, when I built it says 'Build Failed' but there are no errors in the 'Error Tab'. The first line compiles well: using var channel = GrpcChannel.ForAddress("https://localhost:5001"); But when I uncoment the second line give me that strange error: var weather = new Greeter.GreeterClient(channel); Anyone knows what is wrong? I'm using .Net 5.0. Thanks!