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

[Tom]

Dear all,
when I ran the following code, I always got "The underlying connection was closed: An unexpected error occurred on a send" error, it happend at "httpReq.GetResponse();" and the stack trace is
************start of stack trace***************************
The underlying connection was closed: An unexpected error occurred on a send. at System.Net.HttpWebRequest.CheckFinalS
tatus()
at System.Net.HttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
at System.Net.HttpWebRequest.GetResponse()
***********end of stack trace**************88
Much appreciated for any help!
Tom
****************************************************
try
{
HttpWebRequest httpReq = (HttpWebRequest) WebRequest.Create("https://test/kkk");
httpReq.ContentType = "text/xml";
httpReq.Method = "POST";
httpReq.KeepAlive=false;
byte[] requestbody = Encoding.UTF8.GetBytes("<test>kkk</test>");
Stream requestStream = httpReq.GetRequestStream();
int length = requestbody.Length;
requestStream.Write(requestbody,0,length);
requestStream.Close();
X509Certificate x509 = X509Certificate.CreateFromCertFile("C:\\kk\\509cer.cer");
ttpReq.ClientCertificates.Add(x509);
HttpWebResponse webResponse = (HttpWebResponse) httpReq.GetResponse();
}
catch (WebException ex)
{
Response.Write(ex.Message);
}
catch (Exception err)
{
Response.Write(err.Message);
}

 

[Joe Kaplan \(MVP - ADSI\)]

It is very likely an SSL problem. Do you seen any SChannel errors in the
event log? Do you get any certificate warnings when you do the same action
in the browser?

Oftentimes these errors can be overcome by creating a custom
ICertificatePolicy object that ignores the error you are getting, but it is
always better to solve the actual problem instead.

Joe K.

Dear all,
when I ran the following code, I always got "The underlying connection

was closed: An unexpected error occurred on a send" error, it happend at
"httpReq.GetResponse();" and the stack trace is

************start of stack trace***************************
The underlying connection was closed: An unexpected error occurred on a

send. at System.Net.HttpWebRequest.CheckFinalS

tatus()
at System.Net.HttpWebRequest.EndGetResponse(IAsyncResult asyncResult)
at System.Net.HttpWebRequest.GetResponse()
***********end of stack trace**************88
Much appreciated for any help!
Tom
****************************************************
try
{
HttpWebRequest httpReq = (HttpWebRequest) WebRequest.Create("https://test/kkk");
httpReq.ContentType = "text/xml";
httpReq.Method = "POST";
httpReq.KeepAlive=false;
byte[] requestbody = Encoding.UTF8.GetBytes("<test>kkk</test>");
Stream requestStream = httpReq.GetRequestStream();
int length = requestbody.Length;
requestStream.Write(requestbody,0,length);
requestStream.Close();
X509Certificate x509 = X509Certificate.CreateFromCertFile("C:\\kk\\509cer.cer");
ttpReq.ClientCertificates.Add(x509);
HttpWebResponse webResponse = (HttpWebResponse) httpReq.GetResponse();
}
catch (WebException ex)
{
Response.Write(ex.Message);
}
catch (Exception err)
{
Response.Write(err.Message);
}

 

[Tom]

Thanks Joe, After analysing the problem, I found the the connection failed at the handshake phase, I modified the SSLwebclient SDK sample (security SSPI sample) and reproduce the problems. More specifically, it failed at InitializeSecurityContext with the error message "An unknown error happened when processing the certificate"
Now I am checking whether all the certificates were installed correctly

Tom