why NotFound error occur in REST services with windows Phone app? - web-services

Question

i tried to connect REST web servie from windows phone 8 application.
it was working proberly for weeks but after no change in it I get this generic error :
System.Net.WebException: The remote server returned an error:
NotFound.
i tried to test it by online REST Clients and services works properly
i tried to handle Exception and parse it as webException by this code :
var we = ex.InnerException as WebException;
if (we != null)
{
var resp = we.Response as HttpWebResponse;
response.StatusCode = resp.StatusCode;
and i get no more information and final response code is : "NotFound"
any one have any idea about what may cause this error?
there is already a trusted Certificate implemented on the server . the one who has the server suggested to have a DNS entry for the server, this entry should be at the customer DNS or in the phone hosts file .that what i done and worked for awhile but now it doesn't work however i checked that there is no thing changed
this is sample for Get Request it works proberly on Windwos Store apps :
async Task<object> GetHttps(string uri, string parRequest, Type returnType, params string[] parameters)
{
try
{
string strRequest = ConstructRequest(parRequest, parameters);
string encodedRequest = HttpUtility.UrlEncode(strRequest);
string requestURL = BackEndURL + uri + encodedRequest;
HttpWebRequest request = HttpWebRequest.Create(new Uri(requestURL, UriKind.Absolute)) as HttpWebRequest;
request.Headers["applicationName"] = AppName;
request.Headers["applicationPassword"] = AppPassword;
if (AppVersion > 1)
request.Headers["applicationVersion"] = AppVersion.ToString();
request.Method = "GET";
request.CookieContainer = cookieContainer;
var factory = new TaskFactory();
var getResponseTask = factory.FromAsync<WebResponse>(request.BeginGetResponse, request.EndGetResponse, null);
HttpWebResponse response = await getResponseTask as HttpWebResponse;
// string s = response.GetResponseStream().ToString();
if (response.StatusCode == HttpStatusCode.OK)
{
XmlSerializer serializer = new XmlSerializer(returnType);
object obj = serializer.Deserialize(response.GetResponseStream());
return obj;
}
else
{
var Instance = Activator.CreateInstance(returnType);
(Instance as ResponseBase).NetworkError = true;
(Instance as ResponseBase).StatusCode = response.StatusCode;
return Instance;
}
}
catch (Exception ex)
{
return HandleException(ex, returnType);
}
}
i tried to monitor connections from Emulator and i found this error in connection :
**
Authentication failed because the remote party has closed the
transport stream.
**

Answer 1

You saw the client implement a server side certificate in the service. Did you have that certificate installed on the phone? That can be the cause of the NotFound error. Please, can you try to navigate to the service in the phone or emulator internet explorer prior to testing the app? If you do that, you can see the service working in the emulator/phone internet explorer? Maybe at that point internet explorer ask you about installing the certificate and then you can open your app, and it works.
Also remember if you are testing this in the emulator, every time you close it, the state is lost so you need to repeat the operation of installing the certificate again.
Hope this helps.

Answer 2

If you plan to use SSL in production in general public application (not company-distribution app), you need to ensure your certificate has one of the following root authorities:
SSL root certificates for Windows Phone OS 7.1.
When we had same issue, we purchased SSL certificate from one of those providers and after installing it on server we were able to make HTTPS requests to our services with no problem.
If you have company-distribution app, you can use any certificate from company's Root CA.