Mam niestandardowe zadanie msbuild z tym poleceniem:

var workspace = Workspace.LoadStandAloneProject(csprojPath);

Po uruchomieniu generuje następujący błąd:

  System.InvalidCastException was unhandled by user code
  Message=Unable to cast transparent proxy to type 'Roslyn.Utilities.SerializableDataStorage'.
  Source=Roslyn.Services
  StackTrace:
       at Roslyn.Utilities.RemoteServices.CreateInstance[T]()
       at Roslyn.Services.Host.TemporaryStorageServiceFactory.CreateService(IWorkspaceServiceProvider workspaceServices)
       at Roslyn.Services.Host.WorkspaceServiceProviderFactory.Provider.c__DisplayClass7.b__4()
       at Roslyn.Utilities.NonReentrantLazy`1.get_Value()
       at Roslyn.Services.Host.WorkspaceServiceProviderFactory.Provider.GetService[TWorkspaceService]()
       at Roslyn.Services.SolutionServices..ctor(IWorkspaceServiceProvider workspaceServices, ILanguageServiceProviderFactory languageServicesFactory)
       at Roslyn.Services.Solution..ctor(SolutionId id, String filePath, VersionStamp version, VersionStamp latestProjectVersion, ILanguageServiceProviderFactory languageServiceProviderFactory, IWorkspaceServiceProvider workspaceServices)
       at Roslyn.Services.Host.SolutionFactoryServiceFactory.SolutionFactoryService.CreateSolution(SolutionId id)
       at Roslyn.Services.Host.TrackingWorkspace.CreateNewSolution(ISolutionFactoryService solutionFactory, SolutionId id)
       at Roslyn.Services.Host.TrackingWorkspace..ctor(IWorkspaceServiceProvider workspaceServiceProvider, Boolean enableBackgroundCompilation, Boolean enableInProgressSolutions)
       at Roslyn.Services.Host.HostWorkspace..ctor(IWorkspaceServiceProvider workspaceServiceProvider, Boolean enableBackgroundCompilation, Boolean enableInProgressSolutions, Boolean enableFileTracking)
       at Roslyn.Services.Host.LoadedWorkspace..ctor(ILanguageServiceProviderFactory languageServiceProviderFactory, IWorkspaceServiceProvider workspaceServiceProvider, IProjectFileService projectFileFactsService, IDictionary`2 globalProperties, Boolean enableBackgroundCompilation, Boolean enableFileTracking)
       at Roslyn.Services.Host.LoadedWorkspace..ctor(ExportProvider exportProvider, Boolean solutionLoadOnly, Boolean enableFileTracking)
       at Roslyn.Services.Host.LoadedWorkspace..ctor(Boolean enableFileTracking)
       at Roslyn.Services.Host.LoadedWorkspace.LoadStandAloneProject(String projectFileName, String configuration, String platform, String language, Boolean enableFileTracking)
       at Roslyn.Services.Workspace.LoadStandAloneProject(String projectFileName, String configuration, String platform, String language, Boolean enableFileTracking)
       ...

Ten sam kod uruchamiany w aplikacji konsolowej z tym samym projektem działa dobrze.

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