binary/octet-stream

Following code just hangs forever
var r = WebRequest.Create(uri);
r.Method = "POST";
r.ContentType = "binary/octet-stream";

ManualResetEvent re= new ManualResetEvent(false);
r.BeginGetRequestStream(x =>
{
//we neve get here
using(var rs = r.EndGetRequestStream(x)){
rs.Write();
}

re.Set();
}, null);
re.WaitOne();

"binary/octet-stream" is not supported?


Thanks.

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