At work we have a squid proxy and nuget couldn’t connect to the internet because of it. That was a major bummer.

The problem was not very new but hard to solve for someone who does not have a proxy to hide behind. There was already a discussion going on.

So I set about creating a fork.

On my way

First thing to do was to create a fork. Which is easy as pie, just click the create fork link and wait a minute. Then I had to install mercurial since that is what codeplex uses.

After that I cloned my fork locally with hg clone This is the first time I used Mercurial but it is similar to Git.

After that I had a lot of code.

As with all projects you fall into it seems a bit daunting to find what you need. But the code for nuget is pretty decent and finding what I needed to change was pretty easy.

I found out that the code I would probably needed to change was in httpclient.

using System;
using System.Net;
using System.Net.Cache;

namespace NuGet {
    public class HttpClient : IHttpClient {
        public string UserAgent {

        public WebRequest CreateRequest(Uri uri) {
            WebRequest request = WebRequest.Create(uri);
            return request;

        public void InitializeRequest(WebRequest request) {
            var httpRequest = request as HttpWebRequest;
            if (httpRequest != null) {
                httpRequest.UserAgent = UserAgent;
            request.CachePolicy = new HttpRequestCachePolicy();
            request.UseDefaultCredentials = true;
            if (request.Proxy != null) {
                // If we are going through a proxy then just set the default credentials
                request.Proxy.Credentials = CredentialCache.DefaultCredentials;

        public Uri GetRedirectedUri(Uri uri) {
            WebRequest request = CreateRequest(uri);
            using (WebResponse response = request.GetResponse()) {
                if (response == null) {
                    return null;
                return response.ResponseUri;

Since I did not think that I should build the complete project to test my usecase I just planned on building a testproject with the httpclient and a testclass to test my theories. I also do this because I think I might need to ask the user for his credentials instead of taking them from the cache. But first I have to know what errors it produces.

And this was my testharness.

using System;
using System.Data;
using NuGet;

namespace Nuget
    class Program
        static void Main(string[] args)
            var client = new HttpClient();
            var webReq = client.CreateRequest(new Uri(""));
                var stream = webReq.GetResponse().GetResponseStream();
                var dat = new DataSet();
                Console.WriteLine("reading stream");
                Console.WriteLine("writing stream");
            catch (Exception ex)
                Console.WriteLine(ex.GetType().Name + ": " + ex.Message);

Running this the first time (the original code) gave me an Exception.

WebException: The remote server returned an error: (407) Proxy Authentication Required.

So I put a breakpoint on the line that deals with the proxy and should get the credentials out of the cache.

Now I’m pretty sure that cache is related to what IE uses. So I got IE from under the dust and connected to the internet. And tried again.

And here is the result.

I just used the same screenshot as before since their was no difference ;-).

I also tried.

csharp request.Proxy.Credentials = CredentialCache.DefaultNetworkCredentials; With the same result.

So I tried something I know that works for me.

csharp request.Proxy.Credentials = new NetworkCredential(username,password); And that worked. But that would require a major change to the code, because at some point the system will have to ask for the credentials.

SO I came up with this solution.

if (request.Proxy != null)


// If we are going through a proxy then just set the default credentials

request.Proxy.Credentials = CredentialCache.DefaultCredentials;

// if the defaultcredentials are empty we will have to provide them

if (String.IsNullOrEmpty(request.Proxy.Credentials.GetCredential(request.RequestUri,”NTLM”).UserName))


request.Proxy.Credentials = new NetworkCredential(settings.Username, settings.password);



I’m pretty sure the above will not break the NTLM authentication but I can’t test.

but I still need to test it behind a none-proxy and I will have to either make it possible to store the username and password in a config file somewhere or to ask for them on connecting. Asking for them would be the more difficult option. Making it a setting somewhere would be eassier.

Not sure yet if this solved the problem, it did for my little usecase but I could have broken everything and I would need to install Moles to write decent tests, but then again I have no idea what an NTML-enabled proxy will return.

But at least I tried.