I am trying to do a httpwebrequest with a proxy and everytime I try to do it I get this error:

The underlying connection was closed: An unexpected error occurred on a receive.

This is my httpwebrequest code. I removed the postData and the sites I am trying to request to since I am planning to sell my program and dont want leechers to get a hold of my code.

Code:
string MyProxyHostString = txtBoxIP.Text;
int MyProxyPort = System.Convert.ToInt32(txtBoxPort.Text);
 
System.Net.ServicePointManager.Expect100Continue = false;
 
string postdata = "";
 
 
UTF8Encoding encoding1 = new UTF8Encoding();
byte[] bytedata = encoding1.GetBytes(postdata);
 
HttpWebRequest request = (HttpWebRequest)WebRequest.Create("");
request.Proxy = new WebProxy(MyProxyHostString, MyProxyPort);
request.Method = "POST";
request.KeepAlive = false;
request.ContentType = "application/x-www-form-urlencoded";
request.Referer = "";
request.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.8.1.6) Gecko/20070725 Firefox/2.0.0.6";
request.ContentLength = bytedata.Length;
 
 
 
Stream postreqstream2 = request.GetRequestStream();
postreqstream2.Write(bytedata, 0, bytedata.Length);
postreqstream2.Close();
HttpWebResponse response = default(HttpWebResponse);
 
response = (HttpWebResponse)request.GetResponse();
StreamReader stream2 = new StreamReader(response.GetResponseStream());
StreamReader reader2 = new StreamReader(response.GetResponseStream());