Storyboard won't open in Visual Studio (Xamarin). The designer could not be initialized

Question

We use Visual Studio (Xamarin) to develop our Apps for Apple. Since I installed the latest update, the Storyboard wont open in Visual Studio.

I tried downgrading to the last version but that doesn't seem to work. Rebuilded, Restartet and Unloaded the project already.

Error Message:

MonoTouch.Design.Client.CouldNotInitializeRendererException: Exception of type 'MonoTouch.Design.Client.CouldNotInitializeRendererException' was thrown.
   at MonoTouch.Design.Client.ServerProcessConnection.SendRequest(CommandRequest req, Boolean throwIfNotRunning) in E:\A\_work\1898\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 232
   at MonoTouch.Design.Client.ServerProcessConnection.SendRequest[TResponse](CommandRequest req, Boolean throwIfNotRunning) in E:\A\_work\1898\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 243
   at MonoTouch.Design.Client.ServerProcessConnection.CreateSession() in E:\A\_work\1898\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 111
   at MonoTouch.Design.Client.ServerProcessConnection.<CreateSessionAsync>b__28_0() in E:\A\_work\1898\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 116
   at System.Threading.Tasks.Task`1.InnerInvoke()
   at System.Threading.Tasks.Task.Execute()
...
...
...
[2019-10-11 15:43:30.7] INFO: [2019-10-11 15:43:30.6] INFO: Waiting for renderer to start... 300
[2019-10-11 15:43:30.9] INFO: [2019-10-11 15:43:30.9] ERROR: Could not initialize renderer
[2019-10-11 15:43:30.9] INFO: MonoTouch.Design.Client.CouldNotInitializeRendererException: The renderer never started, bailing out... ---> MonoTouch.Design.Client.RetryConnectionException ---> System.Net.Sockets.SocketException: Connection refused
[2019-10-11 15:43:30.9] INFO:   at System.Net.Sockets.Socket.Connect (System.Net.EndPoint remoteEP) [0x000b6] in <118907f5eb5f4e538f3e3bdd8361378f>:0 
[2019-10-11 15:43:30.9] INFO:   at Mono.Unix.UnixClient.Connect (Mono.Unix.UnixEndPoint remoteEndPoint) [0x00006] in <47e71035f6774c5fa65560f4ab0cc60e>:0 
[2019-10-11 15:43:30.9] INFO:   at (wrapper remoting-invoke-with-check) Mono.Unix.UnixClient.Connect(Mono.Unix.UnixEndPoint)
[2019-10-11 15:43:30.9] INFO:   at MonoTouch.Design.Client.Mac.MacServerProcessConnection.SendRequestImpl (MonoTouch.Design.CommandRequest request) [0x0000d] in <75e4a400d63a46619c2379952ad9ffcc>:0 
[2019-10-11 15:43:30.9] INFO:    --- End of inner exception stack trace ---
[2019-10-11 15:43:30.9] INFO:   at MonoTouch.Design.Client.Mac.MacServerProcessConnection.SendRequestImpl (MonoTouch.Design.CommandRequest request) [0x0001b] in <75e4a400d63a46619c2379952ad9ffcc>:0 
[2019-10-11 15:43:30.9] INFO:   at MonoTouch.Design.Client.ServerProcessConnection.SendRequestCore (MonoTouch.Design.CommandRequest request, System.Boolean throwIfNotRunning) [0x00050] in <3fb2608a4c644b7faeb25f7a26ae637f>:0 
[2019-10-11 15:43:30.9] INFO:    --- End of inner exception stack trace ---
[2019-10-11 15:43:30.9] INFO:   at MonoTouch.Design.Client.ServerProcessConnection.SendRequestCore (MonoTouch.Design.CommandRequest request, System.Boolean throwIfNotRunning) [0x000c2] in <3fb2608a4c644b7faeb25f7a26ae637f>:0 
[2019-10-11 15:43:30.9] INFO:   at MonoTouch.Design.Client.ServerProcessConnection.SendRequest (MonoTouch.Design.CommandRequest req, System.Boolean throwIfNotRunning) [0x00000] in <3fb2608a4c644b7faeb25f7a26ae637f>:0 
[2019-10-11 15:43:30.9] INFO:   at CSProxyHost.MainClass.HandleMessage (MonoTouch.Design.CommandRequest message) [0x0015b] in <22267ef404cb4303b2debccd373e2a94>:0 
[2019-10-11 15:43:30.9] INFO: Reloading: Server rendering completed in 61335ms
[2019-10-11 15:43:30.9] ERROR: EnsureSession (counter 1): System.AggregateException: One or more errors occurred. ---> MonoTouch.Design.Client.CouldNotInitializeRendererException: Exception of type 'MonoTouch.Design.Client.CouldNotInitializeRendererException' was thrown.
   at MonoTouch.Design.Client.ServerProcessConnection.SendRequest(CommandRequest req, Boolean throwIfNotRunning) in E:\A\_work\1898\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 232
   at MonoTouch.Design.Client.ServerProcessConnection.SendRequest[TResponse](CommandRequest req, Boolean throwIfNotRunning) in E:\A\_work\1898\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 243
   at MonoTouch.Design.Client.ServerProcessConnection.CreateSession() in E:\A\_work\1898\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 111
   at MonoTouch.Design.Client.ServerProcessConnection.<CreateSessionAsync>b__28_0() in E:\A\_work\1898\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 116
   at System.Threading.Tasks.Task`1.InnerInvoke()
   at System.Threading.Tasks.Task.Execute()
   --- End of inner exception stack trace ---
---> (Inner Exception #0) MonoTouch.Design.Client.CouldNotInitializeRendererException: Exception of type 'MonoTouch.Design.Client.CouldNotInitializeRendererException' was thrown.
   at MonoTouch.Design.Client.ServerProcessConnection.SendRequest(CommandRequest req, Boolean throwIfNotRunning) in E:\A\_work\1898\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 232
   at MonoTouch.Design.Client.ServerProcessConnection.SendRequest[TResponse](CommandRequest req, Boolean throwIfNotRunning) in E:\A\_work\1898\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 243
   at MonoTouch.Design.Client.ServerProcessConnection.CreateSession() in E:\A\_work\1898\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 111
   at MonoTouch.Design.Client.ServerProcessConnection.<CreateSessionAsync>b__28_0() in E:\A\_work\1898\s\Xamarin.Designer.iOS\MonoTouch.Design.Client\Connection\ServerProcessConnection.cs:line 116
   at System.Threading.Tasks.Task`1.InnerInvoke()
   at System.Threading.Tasks.Task.Execute()<---

Answer 1

Report the bug as the Storyboard should open with Visual Studio. In the mean time, you can right click on the file inside you Visual Studio For Mac and open it with "Xcode Interface Builder".