Notice (2018-05-24): bugzilla.xamarin.com is now in
Please join us on
Visual Studio Developer Community and in the
Mono organizations on
GitHub to continue tracking issues. Bugzilla will remain
available for reference in read-only mode. We will continue to work
on open Bugzilla bugs, copy them to the new locations
as needed for follow-up, and add the new items under Related
Our sincere thanks to everyone who has contributed on this bug
tracker over the years. Thanks also for your understanding as we
make these adjustments and improvements for the future.
Please create a new report for Bug 61005 on
Developer Community if you have new
information to add and do not yet see a matching new report.
If the latest results still closely match this report, you can use the
After the Xamarin.iOS app builds and the simulator (iPhone 6s iOS 11.2) is going to launch Visual Studio 2017 becomes unresponsive.
The problem started after the Xcode update to version 9.2.
Visual Studio for Mac 188.8.131.527
Xamarin Agent 184.108.40.2062
Windows 10 version 1709 build 16299.64
Visual Studio 2017 version 15.5
Visual Studio 2017 version 15.5 did not support Xcode 9.2 and there were issues related to the simulator due to this, but we have released an update to support it now. Are you still experiencing this issue with the latest version, 15.5.2?
Yes, I'm still experiencing this issue with Visual Studio 2017 15.5.2 and Visual Studio for Mac 220.127.116.11.
When I launch the simulator it ends with fatal error. The second try launches it but the screen is black. Then I must close the simulator and launch it for the third time. Then it works.
I tried to reset its content and settings, but without any effect.
Framework Version: v4.0.30319
Description: The process was terminated due to an unhandled exception.
Exception Info: System.Threading.SemaphoreFullException
at Xamarin.Messaging.Client.MessagingConnection.OnClientDisconnected(System.Object, System.Net.Mqtt.MqttEndpointDisconnected)
at System.EventHandler`1[[System.__Canon, mscorlib, Version=18.104.22.168, Culture=neutral, PublicKeyToken=b77a5c561934e089]].Invoke(System.Object, System.__Canon)
at System.Net.Mqtt.Sdk.MqttClientImpl.Close(System.Net.Mqtt.DisconnectedReason, System.String)
at System.Reactive.AnonymousSafeObserver`1[[System.__Canon, mscorlib, Version=22.214.171.124, Culture=neutral, PublicKeyToken=b77a5c561934e089]].OnCompleted()
at System.Reactive.ScheduledObserver`1[[System.__Canon, mscorlib, Version=126.96.36.199, Culture=neutral, PublicKeyToken=b77a5c561934e089]].Dispatch(System.Reactive.Disposables.ICancelable)
at System.Reactive.Concurrency.Scheduler+<>c.<ScheduleLongRunning>b__72_0(System.Action`1<System.Reactive.Disposables.ICancelable>, System.Reactive.Disposables.ICancelable)
at System.Reactive.Concurrency.NewThreadScheduler+<>c__DisplayClass7_0`1[[System.__Canon, mscorlib, Version=188.8.131.52, Culture=neutral, PublicKeyToken=b77a5c561934e089]].<ScheduleLongRunning>b__0()
at System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object)
Stack trace added.
Had the same issue, solved by full rebuild - first manually cleaning bin/obj folders in all projects, then rebuild in VS
It helps but the error is back after a few debug/stop cycles. It is very annoying.