how to send a file to any website using vb.net windows application

As Jagan if you have user name & password then you can the file to the sites.
For this you have to use webclient and use upload method.

string uriString = "http://yoursitename.com";
WebClient myWebClient = new WebClient();
string UploadData = "Read the file /data here";
myWebClient.Headers.Add("Content-Type", "application/x-www-form-urlencoded");
byte[] byteArray = Encoding.ASCII.GetBytes(UploadData);
byte[] responseArray = myWebClient.UploadData(uriString, "POST", byteArray);
MessageBox.Show(Encoding.ASCII.GetString(responseArray));

Hope this helps you.