Omnisharp-vscode: Unity Intellisense problem may be caused by C# extension error

[Daytae]

Environment data

```.NET Core SDK (reflecting any global.json):
Version: 3.1.301
Commit: 7feb845744

Runtime Environment:
OS Name: Mac OS X
OS Version: 10.14
OS Platform: Darwin
RID: osx.10.14-x64
Base Path: /usr/local/share/dotnet/sdk/3.1.301/

Host (useful for support):
Version: 3.1.5
Commit: 65cd789777

.NET Core SDKs installed:
3.1.201 [/usr/local/share/dotnet/sdk]
3.1.301 [/usr/local/share/dotnet/sdk]

.NET Core runtimes installed:
Microsoft.AspNetCore.App 3.1.3 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 3.1.5 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
Microsoft.NETCore.App 3.1.3 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]
Microsoft.NETCore.App 3.1.5 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]

To install additional .NET Core runtimes or SDKs:
https://aka.ms/dotnet-download

VS Code version:
1.49.0
C# Extension version:
1.23.2
## OmniSharp log

```Starting OmniSharp server at 9/12/2020, 8:47:42 PM
    Target: /Users/Flickso/mirrormirroronthewall/mirrormirroronthewall.sln

OmniSharp server started.
    Path: /Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/run
    PID: 19986

[info]: OmniSharp.Stdio.Host
        Starting OmniSharp on MacOS 10.14.5 (x64)
[info]: OmniSharp.Services.DotNetCliService
        DotNetPath set to dotnet
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
        Located 1 MSBuild instance(s)
            1: StandAlone 16.8.0 - "/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin"
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
        MSBUILD_EXE_PATH environment variable set to '/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/MSBuild.exe'
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
        Registered MSBuild instance: StandAlone 16.8.0 - "/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin"
            CscToolExe = csc.exe
            MSBuildToolsPath = /Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin
            CscToolPath = /Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Roslyn
            BypassFrameworkInstallChecks = true
            MSBuildExtensionsPath = /Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild
[info]: OmniSharp.Cake.CakeProjectSystem
        Detecting Cake files in '/Users/Flickso/mirrormirroronthewall'.
[info]: OmniSharp.Cake.CakeProjectSystem
        Could not find any Cake files
[info]: OmniSharp.MSBuild.ProjectSystem
        Detecting projects in '/Users/Flickso/mirrormirroronthewall/mirrormirroronthewall.sln'.
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Telepathy.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Websocket.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Cloud.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Components.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Ninja.WebSockets.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Examples.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Runtime.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Examples.Cloud.GUI.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Assembly-CSharp.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Examples.Cloud.Pong.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Common.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Performance.Runtime.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Authenticators.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.example.RigidbodyPhysics.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Tests.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Weaver.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Editor.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Performance.Editor.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/WeaverTestExtraAssembly.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.CompilerSymbols.csproj'
[info]: OmniSharp.MSBuild.ProjectManager
        Queue project update for '/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Generated.csproj'
[info]: OmniSharp.Script.ScriptProjectSystem
        Detecting CSX files in '/Users/Flickso/mirrormirroronthewall'.
[info]: OmniSharp.Script.ScriptProjectSystem
        Could not find any CSX files
[info]: OmniSharp.WorkspaceInitializer
        Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.CSharpFormattingWorkspaceOptionsProvider, Order: 0
[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.csproj
[info]: OmniSharp.WorkspaceInitializer
        Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.Completion.CompletionOptionsProvider, Order: 0
[info]: OmniSharp.WorkspaceInitializer
        Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.RenameWorkspaceOptionsProvider, Order: 100
[info]: OmniSharp.WorkspaceInitializer
        Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.ImplementTypeWorkspaceOptionsProvider, Order: 110
[info]: OmniSharp.WorkspaceInitializer
        Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.BlockStructureWorkspaceOptionsProvider, Order: 140
[info]: OmniSharp.WorkspaceInitializer
        Configuration finished.
[info]: OmniSharp.Stdio.Host
        Omnisharp server running using Stdio at location '/Users/Flickso/mirrormirroronthewall' on host 19907.
[info]: OmniSharp.OmniSharpWorkspace
        Miscellaneous file: /Users/Flickso/mirrormirroronthewall/Assets/agoodtest/Scripts/hgfdsahg.cs added to workspace
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Telepathy.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Telepathy.csproj'.
/Users/Flickso/mirrormirroronthewall/Telepathy.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Websocket.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Websocket.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Websocket.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Cloud.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Cloud.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Cloud.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Components.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Components.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Components.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Ninja.WebSockets.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Ninja.WebSockets.csproj'.
/Users/Flickso/mirrormirroronthewall/Ninja.WebSockets.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Examples.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Examples.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Examples.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Tests.Runtime.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Runtime.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Runtime.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Examples.Cloud.GUI.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Examples.Cloud.GUI.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Examples.Cloud.GUI.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Assembly-CSharp.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Assembly-CSharp.csproj'.
/Users/Flickso/mirrormirroronthewall/Assembly-CSharp.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Examples.Cloud.Pong.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Examples.Cloud.Pong.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Examples.Cloud.Pong.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Tests.Common.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Common.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Common.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Tests.Performance.Runtime.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Performance.Runtime.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Performance.Runtime.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Authenticators.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Authenticators.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Authenticators.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.example.RigidbodyPhysics.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.example.RigidbodyPhysics.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.example.RigidbodyPhysics.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Tests.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Tests.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Tests.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Weaver.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Weaver.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Weaver.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Editor.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Editor.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Editor.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Tests.Performance.Editor.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Performance.Editor.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Performance.Editor.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/WeaverTestExtraAssembly.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/WeaverTestExtraAssembly.csproj'.
/Users/Flickso/mirrormirroronthewall/WeaverTestExtraAssembly.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.CompilerSymbols.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.CompilerSymbols.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.CompilerSymbols.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[info]: OmniSharp.MSBuild.ProjectManager
        Loading project: /Users/Flickso/mirrormirroronthewall/Mirror.Tests.Generated.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
        The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks
[warn]: OmniSharp.MSBuild.ProjectManager
        Failed to load project file '/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Generated.csproj'.
/Users/Flickso/mirrormirroronthewall/Mirror.Tests.Generated.csproj
/Users/Flickso/.vscode/extensions/ms-dotnettools.csharp-1.23.2/.omnisharp/1.37.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1178,5): Error: The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Telepathy.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Websocket.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Cloud.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Components.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Ninja.WebSockets.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Examples.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Tests.Runtime.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Examples.Cloud.GUI.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Assembly-CSharp.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Examples.Cloud.Pong.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Tests.Common.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Tests.Performance.Runtime.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Authenticators.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.example.RigidbodyPhysics.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Tests.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Weaver.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Editor.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Tests.Performance.Editor.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/WeaverTestExtraAssembly.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.CompilerSymbols.csproj
[fail]: OmniSharp.MSBuild.ProjectManager
        Attempted to update project that is not loaded: /Users/Flickso/mirrormirroronthewall/Mirror.Tests.Generated.csproj

Steps to reproduce

Load up VS code with C# extension

Expected behavior

Unity intellisense would work

Actual behavior

C# extension doesn't work and (what I presume happens) is it messes up the unity intellisense

[JoeRobich]

[fail]: OmniSharp.MSBuild.ProjectLoader
The reference assemblies for .NETFramework,Version=v4.7.1 were not found. To resolve this, install the Developer Pack (SDK/Targeting Pack) for this framework version or retarget your application. You can download .NET Framework Developer Packs at https://aka.ms/msbuild/developerpacks

@Daytae Sorry you are running into issues. Unity relies on some .NET Full Framework reference assemblies that are not part of OmniSharp's minimal MSBuild. You will need into install the latest stable Mono for your platform. https://www.mono-project.com/download/stable/

[JoeRobich]

@Daytae I should have mentioned that you will need to set "omnisharp.useGlobalMono" to "always".

[StarrKiss]

@JoeRobich where should I set this? getting similar issue

[Daytae]

I went to preferences and disabled useGlobalMono, but it still isn't working, and my mono version is 6.10

[filipw]

you need to set use global Mono to always, not disable it

[netpoetica]

@Daytae I should have mentioned that you will need to set "omnisharp.useGlobalMono" to "always".

@JoeRobich I can't stress enough, you should really put this in the README - you already have a section https://github.com/OmniSharp/omnisharp-vscode#note-about-using-net-core-31401-or-net-5-preview-8-sdks-on-mono-platforms but I don't think it will be clear to most developers until they really dig, what even the problem is.

My understanding after a lot of frustration is that OmniSharp pulls its own version of dotnet in along with the extension, but that at least in my case on Mac OSX where I have installed Mono and .NET Core, in order to be able to use with Unity, I need to make sure it is using my system version of Mono and not the one omnisharp is bundling? I have to imagine there are a lot of Unity devs on Mac OSX who just got frustrated and walked away from not having auto-complete, because the error messages that show up from Omnisharp are helpful only for windows folks. For example, this call to install the Developer Pack which is available only as an .exe from MS site (https://docs.microsoft.com/en-us/dotnet/framework/install/guide-for-developers) - it is a dead-end for Mac users.

In my case, setting this global config did solve the problem and get me back to auto-complete functioning. Thank you!

[gilisho]

Solved the problem for me as well!
For those wondering where the setting omnisharp.useGlobalMono should be set: go to VSCode, click on Preferences > Settings, and then use the search bar to search for omnisharp.useGlobalMono. Then you should see the dropdown and set it to always. 😀