NotSupportedException in HttpWebRequest on Windows Phone 7 - silverlight

Question

I have a Windows Phone 7 application built with silverlight. This application has been deployed. I've noticed in the log files that occasionally, my user's actions throw a "NotSupportedException". I have not been able to produce this. However, because of my logs, I know that it is happening in the Execute method shown here:
public void Execute()
{
try
{
// 1. Build the query
string serviceUrl = GetServiceUrl;
// 2. Asynchronously execute the query using HttpWebRequest
WebRequest request = HttpWebRequest.Create(serviceUrl);
request.BeginGetResponse(new AsyncCallback(ServiceRequest_Completed), request);
} catch (Exception ex)
{
LogException(ex, "1");
}
}
private void ServiceRequest_Completed(IAsyncResult result)
{
try
{
// 1. Get the response from the service call
WebRequest request = (WebRequest)(result.AsyncState);
WebResponse response = request.EndGetResponse(result);
// 2. Do stuff with response
}
catch (Exception ex)
{
LogException(ex, "2");
}
}
I know it is happening in the Execute method because the "1" is written in the log file instead of the "2" My question is, what would cause this? I looked at the MSDN documentation and it looks like I'm doing what I should be doing. Like I said, I can't reproduce it locally. But I do know that it is happening regularly by different users because of the log files.

Answer 1

There is a previous question with a very similar title - https://stackoverflow.com/questions/4053197/httpwebrequest-leads-me-to-system-notsupportedexception
The answer to that problem seems to have been using ServiceRequest_Completed instead of new AsyncCallback(ServiceRequest_Completed)