OmniSharp
lastmod 2025-02-14created 2020-11-1010 edits
OmniSharp is a family of Open Source projects, each with one goal: To enable a great .NET experience in YOUR editor of choice
Troubleshooting
.NETFramework not found in macOS
After installing the C# plugin, opening a C# file may produce the following error.
Microsoft.Common.CurrentVersion.targets(1175, 5): [MSB3644] 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
Change the C# plugin's Omnisharp: Use Global Mono setting to always.
This project targets .NET version that requires reference assemblies that do not ship with OmniSharp out of the box (e.g. .NET Framework)
/home/yourname/.vscode/extensions/ms-dotnettools.csharp-1.24.1/.omnisharp/1.38.1/omnisharp/.msbuild/Current/Bin/Microsoft.Common.CurrentVersion.targets(1220,5): Error: This project targets .NET version that requires reference assemblies that do not ship with OmniSharp out of the box (e.g. .NET Framework). The most common solution is to make sure Mono is installed on your machine (https://mono-project.com/download/) and that OmniSharp is started with that Mono installation (e.g. "omnisharp.useGlobalMono":"always" in C# Extension for VS Code).
Change the omnisharp.useGlobalMono setting to always.
=== .NETFramework,Version=v4.7.2 were not found === The warning is as follows.
[fail]: OmniSharp.MSBuild.ProjectLoader
The reference assemblies for .NETFramework,Version=v4.7.2 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 '/home/yourname/Project/EduPiano/EduPiano.csproj'.
/home/yourname/Project/EduPiano/EduPiano.csproj
/home/yourname/.vscode-oss/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=v4.7.2 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: /home/yourname/Project/EduPiano/EduPiano.csproj
For reference, godot running on ArchLinux generated the following .csproj file:
<Project Sdk="Godot.NET.Sdk/3.2.3">
<PropertyGroup>
<TargetFramework>net472</TargetFramework>
</PropertyGroup>
</Project>
Check the Target frameworks in SDK-style projects - .NET | Microsoft Docs documentation and modify TargetFramework to use .NET Core. (Check the version with dotnet --version)
<Project Sdk="Godot.NET.Sdk/3.2.3">
<PropertyGroup>
<TargetFramework>netcoreapp3.1</TargetFramework>
</PropertyGroup>
</Project>
This project targets .NET version that requires reference assemblies that are not installed (e.g. .NET Framework)
Starting OmniSharp server at 4/5/2023, 3:02:14 PM
Target: /home/yourname/Project/EduPiano/godot/EduPiano.sln
OmniSharp server started with .NET 6.0.407
.
Path: /home/yourname/.vscode/extensions/ms-dotnettools.csharp-1.25.4-linux-x64/.omnisharp/1.39.4-net6.0/OmniSharp.dll
PID: 168353
[info]: OmniSharp.Stdio.Host
Starting OmniSharp on Unknown 0.0 (Unknown)
[info]: OmniSharp.Services.DotNetCliService
Checking the 'DOTNET_ROOT' environment variable to find a .NET SDK
[info]: OmniSharp.Services.DotNetCliService
Using the 'dotnet' on the PATH.
[info]: OmniSharp.Services.DotNetCliService
DotNetPath set to dotnet
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
Located 1 MSBuild instance(s)
1: .NET Core SDK 6.0.407 17.3.2 - "/usr/share/dotnet/sdk/6.0.407/"
[info]: OmniSharp.MSBuild.Discovery.MSBuildLocator
Registered MSBuild instance: .NET Core SDK 6.0.407 17.3.2 - "/usr/share/dotnet/sdk/6.0.407/"
[info]: OmniSharp.WorkspaceInitializer
Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.CSharpFormattingWorkspaceOptionsProvider, Order: 0
[info]: OmniSharp.Cake.CakeProjectSystem
Detecting Cake files in '/home/yourname/Project/EduPiano/godot'.
[info]: OmniSharp.Cake.CakeProjectSystem
Did not find any Cake files
[info]: OmniSharp.MSBuild.ProjectSystem
Detecting projects in '/home/yourname/Project/EduPiano/godot/EduPiano.sln'.
[info]: OmniSharp.MSBuild.ProjectManager
Queue project update for '/home/yourname/Project/EduPiano/godot/EduPiano.csproj'
[info]: OmniSharp.Script.ScriptProjectSystem
Detecting CSX files in '/home/yourname/Project/EduPiano/godot'.
[info]: OmniSharp.Script.ScriptProjectSystem
Did not find any CSX files
[info]: OmniSharp.WorkspaceInitializer
Configuration finished.
[info]: OmniSharp.Stdio.Host
Omnisharp server running using Stdio at location '/home/yourname/Project/EduPiano/godot' on host 168131.
[info]: OmniSharp.MSBuild.ProjectManager
Loading project: /home/yourname/Project/EduPiano/godot/EduPiano.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
This project targets .NET version that requires reference assemblies that are not installed (e.g. .NET Framework). The most common solution is to make sure Mono is fully updated on your machine (https://mono-project.com/download/) and that you are running the .NET Framework build of OmniSharp (e.g. 'omnisharp.useModernNet': false in C# Extension for VS Code).
[warn]: OmniSharp.MSBuild.ProjectManager
Failed to load project file '/home/yourname/Project/EduPiano/godot/EduPiano.csproj'.
/home/yourname/Project/EduPiano/godot/EduPiano.csproj
/usr/share/dotnet/sdk/6.0.407/Microsoft.Common.CurrentVersion.targets(1220,5): Error: This project targets .NET version that requires reference assemblies that are not installed (e.g. .NET Framework). The most common solution is to make sure Mono is fully updated on your machine (https://mono-project.com/download/) and that you are running the .NET Framework build of OmniSharp (e.g. 'omnisharp.useModernNet': false in C# Extension for VS Code).
[fail]: OmniSharp.MSBuild.ProjectManager
Attempted to update project that is not loaded: /home/yourname/Project/EduPiano/godot/EduPiano.csproj
[warn]: OmniSharp.Roslyn.CSharp.Services.InlayHints.InlayHintService
Inlay hints requested for document not in workspace Location { FileName = /home/yourname/Project/EduPiano/godot/Scene/EPFactoryCollectionUI.cs, Range = Range { Start = Point { Line = 0, Column = 0 }, End = Point { Line = 95, Column = 0 } } }
[warn]: OmniSharp.Roslyn.CSharp.Services.InlayHints.InlayHintService
Inlay hints requested for document not in workspace Location { FileName = /home/yourname/Project/EduPiano/godot/Scene/EPFactoryCollectionUI.cs, Range = Range { Start = Point { Line = 0, Column = 0 }, End = Point { Line = 95, Column = 0 } } }
The line where the error occurred is as follows:
[fail]: OmniSharp.MSBuild.ProjectLoader
This project targets .NET version that requires reference assemblies that are not installed (e.g. .NET Framework). The most common solution is to make sure Mono is fully updated on your machine (https://mono-project.com/download/) and that you are running the .NET Framework build of OmniSharp (e.g. 'omnisharp.useModernNet': false in C# Extension for VS Code).