Question

I am trying to download item that exists in Office 365 SharePoint library using WebcClient.DownloadFile() but i am getting this exception:

Exception :

The remote server returned an error: (403) Forbidden.

Sample code :

NetworkCredential credential = new NetworkCredential("username", "password", "aaa.onmicrosoft.com");
WebClient webClient = new WebClient();
webClient.Credentials = credential;
webClient.DownloadFile(@"https://aaa.sharepoint.com/testDoc/test.pdf", @"c:/test.pdf");

Answer 1

With a bit of help from my friends, I’ve managed to crack this SharePoint on-line authentication stuff 🙂

I was kindly pointed in the direction of this blog post from Wictor Wilén.

And my WebClient call that uses Wictors claims library code…

var claimsHelper = new MsOnlineClaimsHelper(sharepointOnlineUrl, username, password);

var client = new WebClient();
client.Headers[ "Accept" ] = "/";
client.Headers.Add(HttpRequestHeader.UserAgent, "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; .NET CLR 1.0.3705;)");
client.Headers.Add(HttpRequestHeader.Cookie, claimsHelper.CookieContainer.GetCookieHeader(new Uri(sharepointOnlineUrl))  );

var document = client.DownloadString( documentUrl );