HubServer.Program.cs:

public static void Main(string[] args)
{

  getRegistrySettings();

  WebApplicationBuilder builder = WebApplication.CreateBuilder(args);

  // Add services to the container.
  builder.Services.AddRazorPages();
  builder.Services.AddServerSideBlazor();
  builder.Services.AddSingleton<WeatherForecastService>();
  builder.Services.AddResponseCompression(opts =>
  {
    opts.MimeTypes = ResponseCompressionDefaults.MimeTypes.Concat(
        new[] { "application/octet-stream" });
  });

  builder.Services.AddCors(options =>
  {
    options.AddPolicy("CORSPolicy", builder =>
    builder.AllowAnyMethod().AllowAnyHeader().AllowCredentials().SetIsOriginAllowed((hosts) => true));
  });

  WebApplication app = builder.Build();

  // Configure the HTTP request pipeline.
  if (!app.Environment.IsDevelopment())
  {
    app.UseExceptionHandler("/Error");
    // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
    app.UseHsts();
  }

  //CORS need to be enabled for calling SignalR service 
  app.UseCors("CORSPolicy");

  //app.UseHttpsRedirection();

  app.UseStaticFiles();

  app.UseRouting();

  app.MapBlazorHub();

  app.MapHub<MCHub>("/mchub");

  //app.MapFallbackToPage("/_Host");

  app.Run();
}

要访问集线器，我用途：
WPF App：

public MainWindow()
{
    InitializeComponent();

    //const string url = "http://localhost:5289/mchub";
    const string url = "http://192.168.10.120/mcsrhub/mchub";
    var queryString = new Dictionary<string, string>
      {
        { "CreatedBy", "me" },
        { "UserId", "1234" },
        { "MachineName", Environment.MachineName }
      };

    var newUrl = new Uri(QueryHelpers.AddQueryString(url, queryString));

    connection = new HubConnectionBuilder()
        .WithUrl(newUrl) //"http://localhost:5289/mchub") //5181/chathub")
        .WithAutomaticReconnect()
        .Build();

    connection.Reconnecting += (sender) =>
    {
        this.Dispatcher.Invoke(() =>
        {
            var newMessage = "Attempting to reconnect...";
            messages.Items.Add(newMessage);
        });

        return Task.CompletedTask;
    };

    connection.Reconnected += (sender) =>
    {
        this.Dispatcher.Invoke(() =>
        {
            var newMessage = "Reconnected to the server";
            messages.Items.Clear();
            messages.Items.Add(newMessage);
        });

        return Task.CompletedTask;
    };

    connection.Closed += (sender) =>
    {
        this.Dispatcher.Invoke(() =>
        {
            var newMessage = "Connection Closed";
            messages.Items.Add(newMessage);
            openConnection.IsEnabled = true;
            sendMessage.IsEnabled = false;
        });

        return Task.CompletedTask;
    };
}

private async void openConnection_Click(object sender, RoutedEventArgs e)
{
    connection.On<string, string>("ReceiveMessage", (user, message) =>
    {
        this.Dispatcher.Invoke(() =>
        {
            var newMessage = $"{user}: {message}";
            messages.Items.Add(newMessage);
        });
    });

    try
    {

        await connection.StartAsync();
        messages.Items.Add("Connection Started");
        openConnection.IsEnabled = false;
        sendMessage.IsEnabled = true;
    }
    catch (Exception ex)
    {
        messages.Items.Add(ex.Message);
    }
}

private async void sendMessage_Click(object sender, RoutedEventArgs e)
{
    try
    {
        await connection.InvokeAsync("SendMessage",
            "WPF Client", messageInput.Text);
    }
    catch (Exception ex)
    {
        messages.Items.Add(ex.Message);
    }
}

如果我使用localhost作为url，则连接正常。当我在LAN上的另一台机器上使用相同的WPF应用程序并使用服务器IP地址或服务器MachineName时，我得到：

• 连接尝试失败，因为连接的一方在一段时间后没有正确响应，或者建立的连接失败，因为连接的主机没有响应。（192.168.10.120：80）*

我已经禁用了两台机器上运行的AVG，并检查了服务器上的端口80是否打开。我添加了cors引用，但这没有什么区别。
编辑：由IIS托管。