Visual Studio for Mac broken

Question

I am trying to open different Xamarin Solutions that worked before, e.g. the ones from https://github.com/xamarin/dev-days-labs (before vs update), now when I try to open the solution, I get the following fatal exception:

Ide.log says:

ERROR [2017-11-15 08:37:44Z]:ERROR [2017-11-15 08:37:44Z]: Error while

trying to load the project /Users/hoppentt/Documents/Projects/XamarinDevDays/dev-days-labs/Demos/app-tasks/DevDaysTasks.iOS/DevDaysTasks.iOS.csproj System.TypeInitializationException: The type initializer for 'MonoDevelop.CSharp.Project.CSharpProject' threw an exception. ---> System.TypeInitializationException: The type initializer for 'MonoDevelop.Ide.TypeSystem.MonoDevelopWorkspace' threw an exception. ---> System.TypeLoadException: Type Microsoft.CodeAnalysis.VisualBasic.CaseCorrection.VisualBasicCaseCorrectionService has invalid vtable method slot 6 with method none at (wrapper managed-to-native) System.RuntimeType:GetPropertiesByName_native (System.RuntimeType,intptr,System.Reflection.BindingFlags,bool) at System.RuntimeType.GetPropertiesByName (System.String name, System.Reflection.BindingFlags bindingAttr, System.Boolean icase, System.RuntimeType reflectedType) [0x00011] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/corlib/ReferenceSources/RuntimeType.cs:516 at System.RuntimeType.GetPropertyCandidates (System.String name, System.Reflection.BindingFlags bindingAttr, System.Type[] types, System.Boolean allowPrefixLookup) [0x00010] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/referencesource/mscorlib/system/rttype.cs:2881 at System.RuntimeType.GetProperties (System.Reflection.BindingFlags bindingAttr) [0x00000] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/referencesource/mscorlib/system/rttype.cs:3089 at System.Reflection.RuntimeReflectionExtensions.GetRuntimeProperties (System.Type type) [0x00006] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/referencesource/mscorlib/system/reflection/RuntimeReflectionExtensions.cs:25 at System.Composition.TypedParts.Discovery.TypeInspector+d__7.MoveNext () [0x00030] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at System.Composition.TypedParts.Discovery.TypeInspector+d__5.MoveNext () [0x000dc] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at System.Composition.TypedParts.Discovery.TypeInspector.InspectTypeForPart (System.Reflection.TypeInfo type, System.Composition.TypedParts.Discovery.DiscoveredPart& part) [0x00061] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at System.Composition.TypedParts.TypedPartExportDescriptorProvider..ctor (System.Collections.Generic.IEnumerable1[T] types, System.Composition.Convention.AttributedModelProvider attributeContext) [0x00037] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at System.Composition.Hosting.ContainerConfiguration.CreateContainer () [0x00042] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at Microsoft.CodeAnalysis.Host.Mef.MefHostServices.Create (System.Collections.Generic.IEnumerable1[T] assemblies) [0x0001e] in :0 at MonoDevelop.Ide.TypeSystem.MonoDevelopWorkspace..cctor () [0x001f9] in /Users/builder/data/lanes/5144/b604c37c/source/monodevelop/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.TypeSystem/MonoDevelopWorkspace.cs:121 --- End of inner exception stack trace --- at MonoDevelop.CSharp.ProjectSearchCategory.Init () [0x00000] in /Users/builder/data/lanes/5144/b604c37c/source/monodevelop/main/src/addins/CSharpBinding/MonoDevelop.CSharp/ProjectSearchCategory.cs:53 at MonoDevelop.CSharp.Project.CSharpProject.get_TargetRuntime () [0x0002b] in /Users/builder/data/lanes/5144/b604c37c/source/monodevelop/main/src/addins/CSharpBinding/MonoDevelop.CSharp.Project/CSharpProjectExtension.cs:56 --- End of inner exception stack trace --- at (wrapper managed-to-native) System.Reflection.MonoCMethod:InternalInvoke (System.Reflection.MonoCMethod,object,object[],System.Exception&) at System.Reflection.MonoCMethod.InternalInvoke (System.Object obj, System.Object[] parameters) [0x00002] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/corlib/System.Reflection/MonoMethod.cs:661 Error while trying to load the project /Users/hoppentt/Documents/Projects/XamarinDevDays/dev-days-labs/Demos/app-tasks/DevDaysTasks.Droid/DevDaysTasks.Droid.csproj System.TypeInitializationException: The type initializer for 'MonoDevelop.CSharp.Project.CSharpProject' threw an exception. ---> System.TypeInitializationException: The type initializer for 'MonoDevelop.Ide.TypeSystem.MonoDevelopWorkspace' threw an exception. ---> System.TypeLoadException: Type Microsoft.CodeAnalysis.VisualBasic.CaseCorrection.VisualBasicCaseCorrectionService has invalid vtable method slot 6 with method none at (wrapper managed-to-native) System.RuntimeType:GetPropertiesByName_native (System.RuntimeType,intptr,System.Reflection.BindingFlags,bool) at System.RuntimeType.GetPropertiesByName (System.String name, System.Reflection.BindingFlags bindingAttr, System.Boolean icase, System.RuntimeType reflectedType) [0x00011] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/corlib/ReferenceSources/RuntimeType.cs:516 at System.RuntimeType.GetPropertyCandidates (System.String name, System.Reflection.BindingFlags bindingAttr, System.Type[] types, System.Boolean allowPrefixLookup) [0x00010] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/referencesource/mscorlib/system/rttype.cs:2881 at System.RuntimeType.GetProperties (System.Reflection.BindingFlags bindingAttr) [0x00000] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/referencesource/mscorlib/system/rttype.cs:3089 at System.Reflection.RuntimeReflectionExtensions.GetRuntimeProperties (System.Type type) [0x00006] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/referencesource/mscorlib/system/reflection/RuntimeReflectionExtensions.cs:25 at System.Composition.TypedParts.Discovery.TypeInspector+d__7.MoveNext () [0x00030] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at System.Composition.TypedParts.Discovery.TypeInspector+d__5.MoveNext () [0x000dc] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at System.Composition.TypedParts.Discovery.TypeInspector.InspectTypeForPart (System.Reflection.TypeInfo type, System.Composition.TypedParts.Discovery.DiscoveredPart& part) [0x00061] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at System.Composition.TypedParts.TypedPartExportDescriptorProvider..ctor (System.Collections.Generic.IEnumerable1[T] types, System.Composition.Convention.AttributedModelProvider attributeContext) [0x00037] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at System.Composition.Hosting.ContainerConfiguration.CreateContainer () [0x00042] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at Microsoft.CodeAnalysis.Host.Mef.MefHostServices.Create (System.Collections.Generic.IEnumerable1[T] assemblies) [0x0001e] in :0 at MonoDevelop.Ide.TypeSystem.MonoDevelopWorkspace..cctor () [0x001f9] in /Users/builder/data/lanes/5144/b604c37c/source/monodevelop/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.TypeSystem/MonoDevelopWorkspace.cs:121 --- End of inner exception stack trace --- at MonoDevelop.CSharp.ProjectSearchCategory.Init () [0x00000] in /Users/builder/data/lanes/5144/b604c37c/source/monodevelop/main/src/addins/CSharpBinding/MonoDevelop.CSharp/ProjectSearchCategory.cs:53 at MonoDevelop.CSharp.Project.CSharpProject.get_TargetRuntime () [0x0002b] in /Users/builder/data/lanes/5144/b604c37c/source/monodevelop/main/src/addins/CSharpBinding/MonoDevelop.CSharp.Project/CSharpProjectExtension.cs:56 --- End of inner exception stack trace --- at (wrapper managed-to-native) System.Reflection.MonoCMethod:InternalInvoke (System.Reflection.MonoCMethod,object,object[],System.Exception&) at System.Reflection.MonoCMethod.InternalInvoke (System.Object obj, System.Object[] parameters) [0x00002] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/corlib/System.Reflection/MonoMethod.cs:661 FATAL ERROR [2017-11-15 08:37:44Z]: Can't create roslyn workspace System.TypeInitializationException: The type initializer for 'MonoDevelop.Ide.TypeSystem.MonoDevelopWorkspace' threw an exception. ---> System.TypeLoadException: Type Microsoft.CodeAnalysis.VisualBasic.CaseCorrection.VisualBasicCaseCorrectionService has invalid vtable method slot 6 with method none at (wrapper managed-to-native) System.RuntimeType:GetPropertiesByName_native (System.RuntimeType,intptr,System.Reflection.BindingFlags,bool) at System.RuntimeType.GetPropertiesByName (System.String name, System.Reflection.BindingFlags bindingAttr, System.Boolean icase, System.RuntimeType reflectedType) [0x00011] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/corlib/ReferenceSources/RuntimeType.cs:516 at System.RuntimeType.GetPropertyCandidates (System.String name, System.Reflection.BindingFlags bindingAttr, System.Type[] types, System.Boolean allowPrefixLookup) [0x00010] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/referencesource/mscorlib/system/rttype.cs:2881 at System.RuntimeType.GetProperties (System.Reflection.BindingFlags bindingAttr) [0x00000] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/referencesource/mscorlib/system/rttype.cs:3089 at System.Reflection.RuntimeReflectionExtensions.GetRuntimeProperties (System.Type type) [0x00006] in /Users/builder/data/lanes/4992/mono-mac-sdk/external/bockbuild/builds/mono-x64/mcs/class/referencesource/mscorlib/system/reflection/RuntimeReflectionExtensions.cs:25 at System.Composition.TypedParts.Discovery.TypeInspector+d__7.MoveNext () [0x00030] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at System.Composition.TypedParts.Discovery.TypeInspector+d__5.MoveNext () [0x000dc] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at System.Composition.TypedParts.Discovery.TypeInspector.InspectTypeForPart (System.Reflection.TypeInfo type, System.Composition.TypedParts.Discovery.DiscoveredPart& part) [0x00061] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at System.Composition.TypedParts.TypedPartExportDescriptorProvider..ctor (System.Collections.Generic.IEnumerable1[T] types, System.Composition.Convention.AttributedModelProvider attributeContext) [0x00037] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at System.Composition.Hosting.ContainerConfiguration.CreateContainer () [0x00042] in <9aac21a4a3f24063b2b8b59143acddfc>:0 at Microsoft.CodeAnalysis.Host.Mef.MefHostServices.Create (System.Collections.Generic.IEnumerable1[T] assemblies) [0x0001e] in :0 at MonoDevelop.Ide.TypeSystem.MonoDevelopWorkspace..cctor () [0x001f9] in /Users/builder/data/lanes/5144/b604c37c/source/monodevelop/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.TypeSystem/MonoDevelopWorkspace.cs:121 --- End of inner exception stack trace --- at (wrapper managed-to-native) System.Object:__icall_wrapper_mono_generic_class_init (intptr) at MonoDevelop.Ide.TypeSystem.TypeSystemService..cctor () [0x0009f] in /Users/builder/data/lanes/5144/b604c37c/source/monodevelop/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.TypeSystem/TypeSystemService.cs:86

Answer 1

It was MFractor in my case - disabled it and now it works just fine - thanks a ton to @SushiHangover !!!