WebClient.UploadData Authentication issue

[y2ktan]

Hi All,
I try to use WebClient.UploadData to upload a photo with the size less than 1MB to my local IIS.

I setup my IIS by adding a new virtual directory with the write access to the photo (Please refer to the figure below for better understanding).

After that, I edit the photo's directory security by clearing up the anonymous access checkbox and check/tick the Integrated Windows authentication.(Please refer to the figure below)

At the end I write the following code to upload the photo. Assuming that my computer login is compaq, password is 1234abcd without join domain and proxy.

using (WebClient Client = new WebClient())
{
  using(FileStream fs = File.OpenRead("C:\abc.jpg"))
  {
     byte[] data = new byte[fs.Length];
     fs.Read(data, 0, data.Length);
     CredentialCache cache = new CredentialCache();
     Uri UploadPhotoDircectory = new Uri("http://localhost/FFQWS/Photo/");
     string AuthType = "Negotiate";
     cache.Add(UploadPhotoDircectory, AuthType, new System.Net.NetworkCredential("compaq", "1234abcd"));
     Client.Credentials = cache;
     try
     {
        Client.UploadData("http://localhost/FFQWS/Photo/abc.jpg", "PUT", data);
     }
     catch(Exception ex)
     {
        MessageBox.Show(ex.Message);
     }
}

Alas, after UploadData I get the following exception.
The remote server returned an error:(401)Unauthorized
I already searched through the internet and comfirmed that I did insert the valid windows login. Hope that someone can help me to solve the issue. Your help is really very appreciated. Thank you very much. ^^