Trouble downloading a file in C#

Question

I am trying to download a file from a C# application. I have tried two different methods, but both yield the same response: "The remote server returned an error: (401) Unauthorized."

I am pretty sure this is a credentials issue (because of the 401). If I navigate to the url from a browser, and enter the very same credentials provided, the file downloads just fine. In "Attempt 2" (below), for authtype, I have tried: NTLM, Basic, Negotiate, and Digest without any luck.

Does anyone see what I might be doing wrong here?

Thanks for the help!

/*** Attempt 1 Begin ***/
string username = "username";
string password = "password";
string domain = "domain";
string url = @"http://LiveLinkInstance.com/livelink/llisapi.dll/999999/WordDocument.docx?func=doc.Fetch&nodeid=999999&ReadOnly=True&VerNum=-2&nexturl=/livelink/llisapi.dll?func=ll&objId=888888&objAction=browse&viewType=1";  

// Create an instance of WebClient
WebClient client = new WebClient();
client.Proxy = null;

client.Credentials = new System.Net.NetworkCredential(username, password, domain);

client.DownloadFile(new Uri(url), @"C:\FileDownloads\test.txt");
/*** Attempt 1 End ***/

/*** Attempt 2 Begin ***/
string username = "username";
string password = "password";
string domain = "domain";
string url = @"http://LiveLinkInstance.com/livelink/llisapi.dll/999999/WordDocument.docx?func=doc.Fetch&nodeid=999999&ReadOnly=True&VerNum=-2&nexturl=/livelink/llisapi.dll?func=ll&objId=888888&objAction=browse&viewType=1";

HttpWebRequest wr = (HttpWebRequest)WebRequest.Create(url);

string credentials = Convert.ToBase64String(ASCIIEncoding.ASCII.GetBytes(domain + "\\" + username + ":" + password));
wr.Headers.Add("Authorization", "Basic " + credentials);

CredentialCache cc = new CredentialCache();
cc.Add(new Uri(url), "NTLM", new NetworkCredential(username, password, domain));
wr.Credentials = cc;
Stream str = ws.GetResponseStream();
/*** Attempt 2 End ***/

Answer 1

As Amitay said, using fiddler to compare against traffic from browser is the best way to go. BTW, look here on SO - what's happening is OP's case was that request was getting redirected to different location but credentials were not re-passed. So OP did manual redirection to solve the issue.