USB HID hangs on Read() in C#

I managed to get the scale working. In my callback, which runs when scale returns data, I was doing Read which is a blocking call.

So a deadlock was created, and I should have only used ReadReport or Read. Take a look at Mike's example below which he posted here.

using System;
using System.Linq;
using System.Text;
using HidLibrary;

namespace MagtekCardReader
{
    class Program
    {
        private const int VendorId = 0x0801;
        private const int ProductId = 0x0002;

        private static HidDevice _device;

        static void Main()
        {
            _device = HidDevices.Enumerate(VendorId, ProductId).FirstOrDefault();

            if (_device != null)
            {
                _device.OpenDevice();

                _device.Inserted += DeviceAttachedHandler;
                _device.Removed += DeviceRemovedHandler;

                _device.MonitorDeviceEvents = true;

                _device.ReadReport(OnReport);

                Console.WriteLine("Reader found, press any key to exit.");
                Console.ReadKey();

                _device.CloseDevice();
            }
            else
            {
                Console.WriteLine("Could not find reader.");
                Console.ReadKey();
            }
        }

        private static void OnReport(HidReport report)
        {
            if (!_device.IsConnected) {
                return;
            }

            var cardData = new Data(report.Data);

            Console.WriteLine(!cardData.Error ? Encoding.ASCII.GetString(cardData.CardData) : cardData.ErrorMessage);

            _device.ReadReport(OnReport);
        }

        private static void DeviceAttachedHandler()
        {
            Console.WriteLine("Device attached.");
            _device.ReadReport(OnReport);
        }

        private static void DeviceRemovedHandler()
        {
            Console.WriteLine("Device removed.");
        }
    }
}

I cannot help you with your problem, but a while ago I had to integrate a foot switch into an application and I found this USB HID C# library that worked perfectly:

A USB HID Component for C#

Maybe you should give it a try because it is very simple to integrate.