I’ve developed a nice solution to capture Network requests. It works with currently latest version of Selenium Webdriver 2.33.0

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using OpenQA.Selenium;

namespace MyNameSpace
{
    public class BrowserNetworkMonitoringTool
    {
        private readonly NetworkManager manager;
        public List<NetworkRequestSentEventArgs> Requests;
        public List<NetworkResponseReceivedEventArgs> Responses;

        public BrowserNetworkMonitoringTool(IWebDriver driver)
        {
            manager = new NetworkManager(driver);
            Requests = new List<NetworkRequestSentEventArgs>();
            Responses = new List<NetworkResponseReceivedEventArgs>();
        }

        public void StartMonitoring()
        {
             manager.NetworkResponseReceived += ResponseReceivedHandler;
             manager.NetworkRequestSent += ManagerOnNetworkRequestSent;
             var monitor = manager.StartMonitoring();
             monitor.Wait();
        }

        private void ManagerOnNetworkRequestSent(object sender, NetworkRequestSentEventArgs e)
        {
            Requests.Add(e);
        }

        private void ResponseReceivedHandler(object sender, NetworkResponseReceivedEventArgs e)
        {
            Responses.Add(e);
        }

        public void StopMonitoring()
        {
            manager.StopMonitoring();
        }

        public void Clear()
        {
            Requests.Clear();
            Responses.Clear();
        }
    }
}

Example of usage:

 BrowserNetworkMonitoringTool networkMonitoringTool = new BrowserNetworkMonitoringTool(CurrentDriver);
 networkMonitoringTool.StartMonitoring();

 //Do any actions you need to do in your test here
 
 networkMonitoringTool.StopMonitoring();

 var allResponses = networkMonitoringTool.Responses;
 foreach (var response in allResponses)
 {
     var unexpectedErrors = new List<string>();
     if (response.ResponseStatusCode > 302)
     {
         unexpectedErrors.Add($"Response: {response.ResponseUrl} has response code: {response.ResponseStatusCode}");
     }

     if (unexpectedErrors.Any())
     {
         Assert.Fail($"Unexpected errors found: {string.Join(", ", unexpectedErrors)}");
     }
 }