How do I solve a webexception VS returning http response as json object

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C#

JSON

serialization

proxy

I'm on a proxy and I get a WebException while calling a method which should return HTTP response in JSON format.

The error is the following:

Server Error in '/' Application.
404
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Net.WebException: 404

Source Error:

Line 44:             else
Line 45:             {
Line 46:                 throw new WebException(((int)response.StatusCode).ToString());
Line 47:             }
Line 48:         }

What I have tried:

private T GetResult<T>(HttpResponseMessage response)
        {
            if (response.IsSuccessStatusCode)   // code 200
            {
                var content = response.Content.ReadAsStringAsync().Result;   
                return JsonConvert.DeserializeObject<T>(content);
            }
            else
            {
                throw new WebException(((int)response.StatusCode).ToString());
            }
        }