omnisharp-roslyn: Unable to build .NET Core project using OmniSharp with "Exception when creating task: System.IO.FileNotFoundException: Could not load file or assembly 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified."

On windows when building a .NET Core project using gitversion 4.0.1-beta1.50 (uses Utilpack 2.9.1) a command line build (via dotnet build) works fine on SDK 2.1.500… BUT when using vscode and omnisharp 1.32.8 I’m getting failures - meaning that intellisense etc isn’t working for me.

Error message is:

Starting OmniSharp server at 11/29/2018, 6:00:41 PM
    Target: c:\Source\test

OmniSharp server started.
    Path: C:\Users\kiera\.vscode\extensions\ms-vscode.csharp-1.17.1\.omnisharp\1.32.8\OmniSharp.exe
    PID: 2548

[info]: OmniSharp.Stdio.Host
        Starting OmniSharp on Windows 6.2.9200.0 (x64)
[info]: OmniSharp.Services.DotNetCliService
        DotNetPath set to dotnet
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
        Located 1 MSBuild instance(s)
            1: StandAlone 15.0 - "C:\Users\kiera\.vscode\extensions\ms-vscode.csharp-1.17.1\.omnisharp\1.32.8\msbuild\15.0\Bin"
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
        MSBUILD_EXE_PATH environment variable set to 'C:\Users\kiera\.vscode\extensions\ms-vscode.csharp-1.17.1\.omnisharp\1.32.8\msbuild\15.0\Bin\MSBuild.exe'
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
        Registered MSBuild instance: StandAlone 15.0 - "C:\Users\kiera\.vscode\extensions\ms-vscode.csharp-1.17.1\.omnisharp\1.32.8\msbuild\15.0\Bin"
            CscToolExe = csc.exe
            CscToolPath = C:\Users\kiera\.vscode\extensions\ms-vscode.csharp-1.17.1\.omnisharp\1.32.8\msbuild\15.0\Bin\Roslyn
            MSBuildExtensionsPath = C:\Users\kiera\.vscode\extensions\ms-vscode.csharp-1.17.1\.omnisharp\1.32.8\msbuild
            MSBuildToolsPath = C:\Users\kiera\.vscode\extensions\ms-vscode.csharp-1.17.1\.omnisharp\1.32.8\msbuild\15.0\Bin
[info]: OmniSharp.Cake.CakeProjectSystem
        Detecting Cake files in 'c:\Source\test'.
[info]: OmniSharp.Cake.CakeProjectSystem
        Could not find any Cake files
[info]: OmniSharp.WorkspaceInitializer
        Project system 'OmniSharp.DotNet.DotNetProjectSystem' is disabled in the configuration.
[info]: OmniSharp.MSBuild.ProjectSystem
        No solution files found in 'c:\Source\test'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for 'c:\Source\test\test.csproj'
[info]: OmniSharp.Script.ScriptProjectSystem
        Detecting CSX files in 'c:\Source\test'.
[info]: OmniSharp.Script.ScriptProjectSystem
        Could not find any CSX files
[info]: OmniSharp.WorkspaceInitializer
        Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.CSharpWorkspaceOptionsProvider
[info]: OmniSharp.WorkspaceInitializer
        Configuration finished.
[info]: OmniSharp.Stdio.Host
        Omnisharp server running using Stdio at location 'c:\Source\test' on host 13996.
[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: c:\Source\test\test.csproj
Exception when creating task: System.IO.FileNotFoundException: Could not load file or assembly 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.
File name: 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
   at UtilPack.NuGet.AssemblyLoading.NuGetRestorerWrapper.ResolveNuGetPackageAssemblies(String[] packageID, String[] packageVersion, MarshaledResultSetter`1 setter)
   at UtilPack.NuGet.AssemblyLoading.NuGetAssemblyResolverImpl.UseResolver(String[] packageIDs, String[] packageVersions)
   at UtilPack.NuGet.AssemblyLoading.NuGetAssemblyResolverImpl.<LoadNuGetAssemblies>d__11.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at E_UtilPack.<LoadNuGetAssembly>d__7.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at UtilPack.NuGet.MSBuild.NuGetTaskRunnerFactory.LoadTaskType(String taskTypeName, NuGetAssemblyResolver resolver, String packageID, String packageVersion, String assemblyPath, ConstructorInfo& taskConstructor, Object[]& constructorArguments, Boolean& usesDynamicLoading)
   at UtilPack.NuGet.MSBuild.TaskReferenceCreator.CreateTaskReferenceHolder(String taskTypeName, NuGetAssemblyResolver resolver, String packageID, String packageVersion, String assemblyPath, String msbuildFrameworkAssemblyName, ResolverLogger logger)
   at UtilPack.NuGet.MSBuild.TaskReferenceCreator.CreateTaskReferenceHolder(String taskTypeName, NuGetAssemblyResolver resolver, String packageID, String packageVersion, String assemblyPath, String msbuildFrameworkAssemblyName, ResolverLogger logger)
   at UtilPack.NuGet.MSBuild.NuGetTaskRunnerFactory.CreateExecutionHelper(String taskName, XElement taskBodyElement, String taskPackageID, String taskPackageVersion, String taskAssemblyFullPath, String taskAssemblyPathHint, BoundRestoreCommandUser restorer, ResolverLogger resolverLogger, GetFileItemsDelegate getFiles, String assemblyCopyTargetFolder, AppDomainSetup& appDomainSetup)
   at UtilPack.NuGet.MSBuild.NuGetTaskRunnerFactory.<>c__DisplayClass36_5.<Initialize>b__7()

WRN: Assembly binding logging is turned OFF.
To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1.
Note: There is some performance penalty associated with assembly bind failure logging.
To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog].

[fail]: OmniSharp.MSBuild.ProjectLoader
        Exception in initialization: System.IO.FileNotFoundException: Could not load file or assembly 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.
File name: 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
   at UtilPack.NuGet.AssemblyLoading.NuGetRestorerWrapper.ResolveNuGetPackageAssemblies(String[] packageID, String[] packageVersion, MarshaledResultSetter`1 setter)
   at UtilPack.NuGet.AssemblyLoading.NuGetAssemblyResolverImpl.UseResolver(String[] packageIDs, String[] packageVersions)
   at UtilPack.NuGet.AssemblyLoading.NuGetAssemblyResolverImpl.<LoadNuGetAssemblies>d__11.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at E_UtilPack.<LoadNuGetAssembly>d__7.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at UtilPack.NuGet.MSBuild.NuGetTaskRunnerFactory.LoadTaskType(String taskTypeName, NuGetAssemblyResolver resolver, String packageID, String packageVersion, String assemblyPath, ConstructorInfo& taskConstructor, Object[]& constructorArguments, Boolean& usesDynamicLoading)
   at UtilPack.NuGet.MSBuild.TaskReferenceCreator.CreateTaskReferenceHolder(String taskTypeName, NuGetAssemblyResolver resolver, String packageID, String packageVersion, String assemblyPath, String msbuildFrameworkAssemblyName, ResolverLogger logger)
   at UtilPack.NuGet.MSBuild.TaskReferenceCreator.CreateTaskReferenceHolder(String taskTypeName, NuGetAssemblyResolver resolver, String packageID, String packageVersion, String assemblyPath, String msbuildFrameworkAssemblyName, ResolverLogger logger)
   at UtilPack.NuGet.MSBuild.NuGetTaskRunnerFactory.CreateExecutionHelper(String taskName, XElement taskBodyElement, String taskPackageID, String taskPackageVersion, String taskAssemblyFullPath, String taskAssemblyPathHint, BoundRestoreCommandUser restorer, ResolverLogger resolverLogger, GetFileItemsDelegate getFiles, String assemblyCopyTargetFolder, AppDomainSetup& appDomainSetup)
   at UtilPack.NuGet.MSBuild.NuGetTaskRunnerFactory.<>c__DisplayClass36_5.<Initialize>b__7()
   at System.Lazy`1.CreateValue()
   at System.Lazy`1.LazyInitValue()
   at UtilPack.NuGet.MSBuild.NuGetTaskRunnerFactory.Initialize(String taskName, IDictionary`2 parameterGroup, String taskBody, IBuildEngine taskFactoryLoggingHost)

WRN: Assembly binding logging is turned OFF.
To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1.
Note: There is some performance penalty associated with assembly bind failure logging.
To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog].

[fail]: OmniSharp.MSBuild.ProjectLoader
        The task factory "UtilPack.NuGet.MSBuild.NuGetTaskRunnerFactory" could not be loaded from the assembly "C:\Users\kiera\.nuget\packages\utilpack.nuget.msbuild\2.9.1\build\\net46\UtilPack.NuGet.MSBuild.dll". Could not load file or assembly 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file 'c:\Source\test\test.csproj'.
c:\Source\test\test.csproj
null(-1,-1): Error: Exception in initialization: System.IO.FileNotFoundException: Could not load file or assembly 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.
File name: 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
   at UtilPack.NuGet.AssemblyLoading.NuGetRestorerWrapper.ResolveNuGetPackageAssemblies(String[] packageID, String[] packageVersion, MarshaledResultSetter`1 setter)
   at UtilPack.NuGet.AssemblyLoading.NuGetAssemblyResolverImpl.UseResolver(String[] packageIDs, String[] packageVersions)
   at UtilPack.NuGet.AssemblyLoading.NuGetAssemblyResolverImpl.<LoadNuGetAssemblies>d__11.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at E_UtilPack.<LoadNuGetAssembly>d__7.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at UtilPack.NuGet.MSBuild.NuGetTaskRunnerFactory.LoadTaskType(String taskTypeName, NuGetAssemblyResolver resolver, String packageID, String packageVersion, String assemblyPath, ConstructorInfo& taskConstructor, Object[]& constructorArguments, Boolean& usesDynamicLoading)
   at UtilPack.NuGet.MSBuild.TaskReferenceCreator.CreateTaskReferenceHolder(String taskTypeName, NuGetAssemblyResolver resolver, String packageID, String packageVersion, String assemblyPath, String msbuildFrameworkAssemblyName, ResolverLogger logger)
   at UtilPack.NuGet.MSBuild.TaskReferenceCreator.CreateTaskReferenceHolder(String taskTypeName, NuGetAssemblyResolver resolver, String packageID, String packageVersion, String assemblyPath, String msbuildFrameworkAssemblyName, ResolverLogger logger)
   at UtilPack.NuGet.MSBuild.NuGetTaskRunnerFactory.CreateExecutionHelper(String taskName, XElement taskBodyElement, String taskPackageID, String taskPackageVersion, String taskAssemblyFullPath, String taskAssemblyPathHint, BoundRestoreCommandUser restorer, ResolverLogger resolverLogger, GetFileItemsDelegate getFiles, String assemblyCopyTargetFolder, AppDomainSetup& appDomainSetup)
   at UtilPack.NuGet.MSBuild.NuGetTaskRunnerFactory.<>c__DisplayClass36_5.<Initialize>b__7()
   at System.Lazy`1.CreateValue()
   at System.Lazy`1.LazyInitValue()
   at UtilPack.NuGet.MSBuild.NuGetTaskRunnerFactory.Initialize(String taskName, IDictionary`2 parameterGroup, String taskBody, IBuildEngine taskFactoryLoggingHost)

WRN: Assembly binding logging is turned OFF.
To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1.
Note: There is some performance penalty associated with assembly bind failure logging.
To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog].

C:\Users\kiera\.nuget\packages\gitversiontask\4.0.1-beta1-50\build\functionality\GitVersionBuild.targets(6,5): Error: The task factory "UtilPack.NuGet.MSBuild.NuGetTaskRunnerFactory" could not be loaded from the assembly "C:\Users\kiera\.nuget\packages\utilpack.nuget.msbuild\2.9.1\build\\net46\UtilPack.NuGet.MSBuild.dll". Could not load file or assembly 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. The system cannot find the file specified.

[fail]: OmniSharp.MSBuild.ProjectManager
        Attemped to update project that is not loaded: c:\Source\test\test.csproj

Originally reported here: https://github.com/stazz/UtilPack/issues/35 & https://github.com/GitTools/GitVersion/issues/1503. I found this whilst trying to get the nuget package gitversiontask working to automatically stamp my assemblies with semver based on the current git state. Gitversiontask uses UtilPack under the covers to perform some MSBuild actions. Both myself and the maintainer of UtilPack are stumped.

I have managed to build a very simple repro that is attached (literally just a new console project with the appropriate packages added and initialised as a git repo). Originally we thought that https://github.com/OmniSharp/omnisharp-roslyn/issues/1094 might be the issue here but we have discounted that as you can probably tell from the log above.

test.zip

Any ideas?

Can we enquire just how omnisharp interacts with msbuild? The Utilpack maintainer is having a hard time figuring that out right now - and that seems to be the area where we have an issue.