title: Xamarin.Forms iOS mTouch Error
body: <p>I am developing an application at ESRI ArcGIS Runtime (Xamarin.Forms [Shared]). I am using a default ArcGIS template in Visual Studio. When i run the app for IOS, it runs successfully but whenever i zoom in 4-5 times, the application returns me the error below and i added xamarin log file. I think it is not about Esri ArcGIS Runtime, it is about Xamarin iOS Touch. How can i fix that?</p>
  
  <p>This errors in Visual Studio 2015 Output:</p>
  
  <pre><code>2017-02-23 14:43:37.330 UniversalApp1[19079:218799] 
  Unhandled Exception:
  System.NullReferenceException: Object reference not set to an instance of an object
    at System.Net.Http.NSUrlSessionHandler+NSUrlSessionHandlerDelegate.DidReceiveData (Foundation.NSUrlSession session, Foundation.NSUrlSessionDataTask dataTask, Foundation.NSData data) [0x00008] in /Users/builder/data/lanes/3985/35d1ccd0/source/xamarin-macios/src/Foundation/NSUrlSessionHandler.cs:267 
  2017-02-23 14:43:37.337 UniversalApp1[19079:218799] Unhandled managed exception:
  Object reference not set to an instance of an object (System.NullReferenceException)
    at System.Net.Http.NSUrlSessionHandler+NSUrlSessionHandlerDelegate.DidReceiveData (Foundation.NSUrlSession session, Foundation.NSUrlSessionDataTask dataTask, Foundation.NSData data) [0x00008] in /Users/builder/data/lanes/3985/35d1ccd0/source/xamarin-macios/src/Foundation/NSUrlSessionHandler.cs:267 
  2017-02-23 14:43:37.338 UniversalApp1[19079:218799] critical: Stacktrace:
  
  2017-02-23 14:43:37.338 UniversalApp1[19079:218799] critical: 
  Native stacktrace:
  2017-02-23 14:43:37.382 UniversalApp1[19079:218799] critical:   0   UniversalApp1                       0x0000000107b34dfd mono_handle_native_sigsegv + 253
  2017-02-23 14:43:37.382 UniversalApp1[19079:218799] critical:   1   libsystem_platform.dylib            0x0000000111427bba _sigtramp + 26
  2017-02-23 14:43:37.382 UniversalApp1[19079:218799] critical:   2   libsystem_kernel.dylib              0x00000001113eb430 libsystem_kernel.dylib + 1072
  2017-02-23 14:43:37.383 UniversalApp1[19079:218799] critical:   3   libsystem_c.dylib                   0x000000011117efd7 abort + 129
  2017-02-23 14:43:37.383 UniversalApp1[19079:218799] critical:   4   UniversalApp1                       0x0000000107ccc61f xamarin_unhandled_exception_handler + 47
  2017-02-23 14:43:37.383 UniversalApp1[19079:218799] critical:   5   UniversalApp1                       0x0000000107b965fb mono_invoke_unhandled_exception_hook + 139
  2017-02-23 14:43:37.383 UniversalApp1[19079:218799] critical:   6   UniversalApp1                       0x0000000107b3464f mono_handle_exception_internal + 5135
  2017-02-23 14:43:37.384 UniversalApp1[19079:218799] critical:   7   UniversalApp1                       0x00000001
  07b33238 mono_handle_exception + 24
  2017-02-23 14:43:37.384 UniversalApp1[19079:218799] critical:   8   UniversalApp1                       0x0000000107aa9e0b altstack_handle_and_restore + 59
  2017-02-23 14:43:37.384 UniversalApp1[19079:218799] critical:   9   ???                                 0x0000000121bac5b8 0x0 + 4860855736
  2017-02-23 14:43:37.384 UniversalApp1[19079:218799] critical:   10  UniversalApp1                       0x0000000107b45387 mono_jit_runtime_invoke + 2247
  2017-02-23 14:43:37.385 UniversalApp1[19079:218799] critical:   11  UniversalApp1                       0x0000000107bfa018 do_runtime_invoke + 88
  2017-02-23 14:43:37.385 UniversalApp1[19079:218799] critical:   12  UniversalApp1                       0x0000000107bf9f90 mono_runtime_invoke + 208
  2017-02-23 14:43:37.385 UniversalApp1[19079:218799] critical:   13  UniversalApp1                       0x0000000107cd15c5 xamarin_invoke_trampoline + 5589
  2017-02-23 14:43:37.385 UniversalApp1[19079:218799] critical:   14  UniversalApp1             
            0x0000000107cd917d xamarin_arch_trampoline + 189
  2017-02-23 14:43:37.386 UniversalApp1[19079:218799] critical:   15  UniversalApp1                       0x0000000107cda531 xamarin_x86_64_common_trampoline + 110
  2017-02-23 14:43:37.386 UniversalApp1[19079:218799] critical:   16  CFNetwork                           0x000000010f9ec88c __67-[NSURLSession delegate_dataTask:didReceiveData:completionHandler:]_block_invoke.242 + 38
  2017-02-23 14:43:37.386 UniversalApp1[19079:218799] critical:   17  Foundation                          0x00000001098149ad __NSBLOCKOPERATION_IS_CALLING_OUT_TO_A_BLOCK__ + 7
  2017-02-23 14:43:37.386 UniversalApp1[19079:218799] critical:   18  Foundation                          0x000000010981468f -[NSBlockOperation main] + 101
  2017-02-23 14:43:37.387 UniversalApp1[19079:218799] critical:   19  Foundation                          0x0000000109812d8c -[__NSOperationInternal _start:] + 672
  2017-02-23 14:43:37.387 UniversalApp1[19079:218799] critical:   20  Foundation                        
    0x000000010980eccf __NSOQSchedule_f + 201
  2017-02-23 14:43:37.387 UniversalApp1[19079:218799] critical:   21  libdispatch.dylib                   0x000000011108d12e _dispatch_client_callout + 8
  2017-02-23 14:43:37.387 UniversalApp1[19079:218799] critical:   22  libdispatch.dylib                   0x00000001110724cf _dispatch_queue_serial_drain + 1018
  2017-02-23 14:43:37.388 UniversalApp1[19079:218799] critical:   23  libdispatch.dylib                   0x0000000111072c9f _dispatch_queue_invoke + 1118
  2017-02-23 14:43:37.388 UniversalApp1[19079:218799] critical:   24  libdispatch.dylib                   0x00000001110749dc _dispatch_root_queue_drain + 506
  2017-02-23 14:43:37.388 UniversalApp1[19079:218799] critical:   25  libdispatch.dylib                   0x0000000111074782 _dispatch_worker_thread3 + 113
  2017-02-23 14:43:37.388 UniversalApp1[19079:218799] critical:   26  libsystem_pthread.dylib             0x0000000111439712 _pthread_wqthread + 1299
  2017-02-23 14:43:37.389 UniversalApp1[19079:218799] critical:   2
  7  libsystem_pthread.dylib             0x00000001114391ed start_wqthread + 13
  2017-02-23 14:43:37.389 UniversalApp1[19079:218799] critical: 
  =================================================================
  Got a SIGABRT while executing native code. This usually indicates
  a fatal error in the mono runtime or one of the native libraries 
  used by your application.
  =================================================================
  The app has been terminated.
  Launch failed. The app 'UniversalApp1.iOS' could not be launched on 'iPhone SE iOS 10.2'. Error: An error occurred while executing MTouch. Please check the logs for more details.
  The app has been terminated.
  </code></pre>
  
  <p>This part in Xamarin Logs</p>
  
  <pre><code>Xamarin.Messaging.Client.MessagingClient Error: 0 : [2017-02-23 14:43:39.9721] An error occured on the receiver while executing a post for topic xvs/idb/4.2.2.11/launch-app and client vs4120Sinan
  Xamarin.Messaging.Exceptions.MessagingRemoteException: An error occured on client IDB42211 while executing a reply for topic xvs/idb/4.2.2.11/launch-app ---&gt; Xamarin.Messaging.Exceptions.MonotouchException: An error occurred while executing MTouch
    at Xamarin.Messaging.IDB.MTouch+&lt;RunAsync&gt;d__8.MoveNext () [0x0024a] in &lt;b3b99d4df65f4615ba6dd9add880a191&gt;:0 
  --- End of stack trace from previous location where exception was thrown ---
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 
    at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x00047] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:187 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:156 
    at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:128 
    at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:535 
    at Xamarin.Messaging.IDB.MTouch+&lt;RunAsync&gt;d__7.MoveNext () [0x0007b] in &lt;b3b99d4df65f4615ba6dd9add880a191&gt;:0 
  --- End of stack trace from previous location where exception was thrown ---
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 
    at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x00047] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:187 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:156 
    at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:128 
    at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:535 
    at Xamarin.Messaging.IDB.MTouch+&lt;LaunchAsync&gt;d__5.MoveNext () [0x000bd] in &lt;b3b99d4df65f4615ba6dd9add880a191&gt;:0 
  --- End of stack trace from previous location where exception was thrown ---
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 
    at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x00047] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:187 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:156 
    at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:128 
    at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:535 
    at Xamarin.Messaging.IDB.Handlers.LaunchAppMessageHandler+&lt;RunMTouchAsync&gt;d__17.MoveNext () [0x00150] in &lt;b3b99d4df65f4615ba6dd9add880a191&gt;:0 
  --- End of stack trace from previous location where exception was thrown ---
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 
    at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x00047] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:187 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:156 
    at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:128 
    at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:535 
    at Xamarin.Messaging.IDB.Handlers.LaunchAppMessageHandler+&lt;ExecuteOnSimulatorAsync&gt;d__13.MoveNext () [0x00086] in &lt;b3b99d4df65f4615ba6dd9add880a191&gt;:0 
  --- End of stack trace from previous location where exception was thrown ---
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 
    at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x00047] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:187 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:156 
    at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:128 
    at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:535 
    at Xamarin.Messaging.IDB.Handlers.LaunchAppMessageHandler+&lt;ExecuteAsync&gt;d__12.MoveNext () [0x00092] in &lt;b3b99d4df65f4615ba6dd9add880a191&gt;:0 
  --- End of stack trace from previous location where exception was thrown ---
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 
    at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x00047] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:187 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:156 
    at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:128 
    at System.Runtime.CompilerServices.TaskAwaiter`1[TResult].GetResult () [0x00000] in &lt;f712f98eb8e445c8918edaf595bbe465&gt;:0 
    at Xamarin.Messaging.Client.RequestHandler`2+&lt;HandleAsync&gt;d__5[TMessage,TResult].MoveNext () [0x0011a] in &lt;3ff57b845ff7490198f5f40dfdc63104&gt;:0 
  --- End of stack trace from previous location where exception was thrown ---
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 
    at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x00047] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:187 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:156 
    at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:128 
    at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in &lt;f712f98eb8e445c8918edaf595bbe465&gt;:0 
    at Xamarin.Messaging.Client.MessageHandlerManager+&lt;&gt;c__DisplayClass17_0`2+&lt;&lt;RegisterHandlerAsync&gt;b__1&gt;d[TMessage,TResult].MoveNext () [0x000b3] in &lt;3ff57b845ff7490198f5f40dfdc63104&gt;:0 
  --- End of stack trace from previous location where exception was thrown ---
    at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw () [0x0000c] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/exceptionservices/exceptionservicescommon.cs:143 
    at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (System.Threading.Tasks.Task task) [0x00047] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:187 
    at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification (System.Threading.Tasks.Task task) [0x0002e] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:156 
    at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd (System.Threading.Tasks.Task task) [0x0000b] in /private/tmp/source-mono-4.8.0/bockbuild-mono-4.8.0-branch/profiles/mono-mac-xamarin/build-root/mono-x86/mcs/class/referencesource/mscorlib/system/runtime/compilerservices/TaskAwaiter.cs:128 
    at System.Runtime.CompilerServices.ConfiguredTaskAwaitable`1+ConfiguredTaskAwaiter[TResult].GetResult () [0x00000] in &lt;f712f98eb8e445c8918edaf595bbe465&gt;:0 
    at Xamarin.Messaging.Client.MessagingClient+&lt;ReplyAsync&gt;d__34`2[TRequest,TResponse].MoveNext () [0x000cf] in &lt;3ff57b845ff7490198f5f40dfdc63104&gt;:0 
     --- End of inner exception stack trace ---
     at Xamarin.Messaging.Client.MessagingClient.&lt;PostAsync&gt;d__23`2.MoveNext()
  </code></pre>
  
  <ul>
  <li>Visual Studio 2015 Community ( Version: 14.0.25431.01 Update 3 )</li>
  <li>Xamarin 4.2.0 ( Xamarin.Android 7.0 – Xamarin.iOS 10.2 )</li>
  <li>ArcGIS Runtime 100 .Net SDK</li>
  </ul>
  
  <p>Thanks in advance,
  Sinan</p>