omnisharp error

[dreamMoli]

When I open c# project ,omnisharp error...

Environment data

dotnet --info output:
.NET SDK (reflecting any global.json):
Version: 7.0.100-preview.3.22179.4
Commit: c48f2c30ee

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/7.0.100-preview.3.22179.4/

Host (useful for support):
Version: 7.0.0-preview.3.22175.4
Commit: 162f83657c

.NET SDKs installed:
7.0.100-preview.3.22179.4 [/usr/local/share/dotnet/sdk]

.NET runtimes installed:
Microsoft.AspNetCore.App 7.0.0-preview.3.22178.4 [/usr/local/share/dotnet/shared/Microsoft.AspNetCore.App]
Microsoft.NETCore.App 7.0.0-preview.3.22175.4 [/usr/local/share/dotnet/shared/Microsoft.NETCore.App]

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

VS Code version:
Version: 1.67.0-insider
Commit: e7c6ad74aff28965d0189ca1dd584f5e9829cf06
Date: 2022-04-19T05:18:48.693Z (2 days ago)
Electron: 17.4.0
Chromium: 98.0.4758.141
Node.js: 16.13.0
V8: 9.8.177.13-electron.0
OS: Darwin x64 18.5.0

C# Extension version: v1.24.4

mono version:
Mono JIT compiler version 6.12.0.174 (2020-02/adf1bc4335d Tue Mar 22 17:57:38 EDT 2022)
Copyright (C) 2002-2014 Novell, Inc, Xamarin Inc and Contributors. www.mono-project.com
TLS:
SIGSEGV: altstack
Notification: kqueue
Architecture: amd64
Disabled: none
Misc: softdebug
Interpreter: yes
LLVM: yes(610)
Suspend: hybrid
GC: sgen (concurrent by default)

OmniSharp log

if omnisharp config:
"omnisharp.path": "latest",
"omnisharp.useGlobalMono": "never",
"omnisharp.projectLoadTimeout":500,

Starting OmniSharp server at 4/21/2022, 1:52:05 PM
Target: /Users/gtl/Desktop/testrunner/testomnisharp

OmniSharp server started.
Path: /Users/gtl/.vscode-insiders/extensions/ms-dotnettools.csharp-1.24.4-darwin-x64/.omnisharp/1.38.3-beta.67/run
PID: 23384

System.TypeInitializationException: The type initializer for 'System.ComponentModel.TypeDescriptor' threw an exception. ---> System.TypeInitializationException: The type initializer for 'Sys' threw an exception. ---> System.DllNotFoundException: System.Native assembly: type: member:(null)
at (wrapper managed-to-native) Interop+Sys.LChflagsCanSetHiddenFlag()
at Interop+Sys..cctor () [0x00000] in <0e2013ab6b944e008349d8dcd759ab4d>:0
--- End of inner exception stack trace ---
at Interop.GetRandomBytes (System.Byte* buffer, System.Int32 length) [0x00000] in <0e2013ab6b944e008349d8dcd759ab4d>:0
at System.Guid.NewGuid () [0x00000] in <0e2013ab6b944e008349d8dcd759ab4d>:0
at System.ComponentModel.TypeDescriptor..cctor () [0x00034] in <81c889a3fdaf408aacac8a870695982b>:0
--- End of inner exception stack trace ---
at OmniSharp.Internal.CommandOptionExtensions.GetValueOrDefault[T] (McMaster.Extensions.CommandLineUtils.CommandOption opt, T defaultValue) [0x00008] in <55b1ee2aa809491890804938d5fc6a47>:0
at OmniSharp.Stdio.StdioCommandLineApplication.get_Encoding () [0x00000] in <6debec82860f43eba1d26ab7fda26428>:0
at OmniSharp.Stdio.Driver.Program+<>c__DisplayClass0_1.

b__1 () [0x00000] in <65498930c054400fad9067d1e841386d>:0
at OmniSharp.CommandLineApplication+<>c__DisplayClass12_0.b__0 () [0x0000b] in <55b1ee2aa809491890804938d5fc6a47>:0
at McMaster.Extensions.CommandLineUtils.CommandLineApplication+<>c__DisplayClass146_0.b__0 (System.Threading.CancellationToken _) [0x00000] in :0
at McMaster.Extensions.CommandLineUtils.CommandLineApplication.ExecuteAsync (System.String[] args, System.Threading.CancellationToken cancellationToken) [0x000bf] in :0
at McMaster.Extensions.CommandLineUtils.CommandLineApplication.Execute (System.String[] args) [0x00016] in :0
at OmniSharp.CommandLineApplication.Execute (System.String[] args) [0x00081] in <55b1ee2aa809491890804938d5fc6a47>:0
at OmniSharp.Stdio.Driver.Program+<>c__DisplayClass0_0.b__0 () [0x00028] in <65498930c054400fad9067d1e841386d>:0
at OmniSharp.HostHelpers.Start (System.Func`1[TResult] action) [0x0001c] in <55b1ee2aa809491890804938d5fc6a47>:0

if omnisharp config:
"omnisharp.path": "latest",
"omnisharp.useGlobalMono": "always",
"omnisharp.projectLoadTimeout":500,

Starting OmniSharp server at 4/21/2022, 2:24:55 PM
Target: /Users/gtl/Desktop/testrunner/testomnisharp

OmniSharp server started with Mono 6.12.0.
Path: /Users/gtl/.vscode-insiders/extensions/ms-dotnettools.csharp-1.24.4-darwin-x64/.omnisharp/1.38.3-beta.67/omnisharp/OmniSharp.exe
PID: 32694

Starting OmniSharp on MacOS 10.14.4 (x64)
info: OmniSharp.Services.DotNetCliService
Checking the 'DOTNET_ROOT' environment variable to find a .NET SDK
info: OmniSharp.Services.DotNetCliService
DotNetPath set to /usr/local/share/dotnet/dotnet
info: OmniSharp.MSBuild.Discovery.MSBuildLocator
Located 1 MSBuild instance(s)
1: Mono 16.10.1 - "/Library/Frameworks/Mono.framework/Versions/6.12.0/lib/mono/msbuild/Current/bin"
info: OmniSharp.MSBuild.Discovery.MSBuildLocator
Registered MSBuild instance: Mono 16.10.1 - "/Library/Frameworks/Mono.framework/Versions/6.12.0/lib/mono/msbuild/Current/bin"
info: OmniSharp.WorkspaceInitializer
Invoking Workspace Options Provider: OmniSharp.Roslyn.CSharp.Services.CSharpFormattingWorkspaceOptionsProvider, Order: 0
info: OmniSharp.Cake.CakeProjectSystem
Detecting Cake files in '/Users/gtl/Desktop/testrunner/testomnisharp'.
info: OmniSharp.Cake.CakeProjectSystem
Did not find any Cake files
info: OmniSharp.MSBuild.ProjectSystem
No solution files found in '/Users/gtl/Desktop/testrunner/testomnisharp'
info: OmniSharp.MSBuild.ProjectManager
Queue project update for '/Users/gtl/Desktop/testrunner/testomnisharp/testomnisharp.csproj'
info: OmniSharp.Script.ScriptProjectSystem
Detecting CSX files in '/Users/gtl/Desktop/testrunner/testomnisharp'.
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 '/Users/gtl/Desktop/testrunner/testomnisharp' on host 32367.
info: OmniSharp.MSBuild.ProjectManager
Loading project: /Users/gtl/Desktop/testrunner/testomnisharp/testomnisharp.csproj
[fail]: OmniSharp.MSBuild.ProjectLoader
The reference assemblies for ".NETFramework,Version=v7.0" were not found. You might be using an older .NET SDK to target .NET 5.0 or higher. Update Visual Studio and/or your .NET SDK.
[warn]: OmniSharp.MSBuild.ProjectManager
Failed to load project file '/Users/gtl/Desktop/testrunner/testomnisharp/testomnisharp.csproj'.
/Users/gtl/Desktop/testrunner/testomnisharp/testomnisharp.csproj
/Library/Frameworks/Mono.framework/Versions/6.12.0/lib/mono/msbuild/Current/bin/Microsoft.Common.CurrentVersion.targets(1232,5): Error: The reference assemblies for ".NETFramework,Version=v7.0" were not found. You might be using an older .NET SDK to target .NET 5.0 or higher. Update Visual Studio and/or your .NET SDK.

Steps to reproduce

open a C# project

Expected behavior

Omnisharp starts

Actual behavior

Omnisharp error

[filipw]

"omnisharp.useGlobalMono": "never", is no longer used in the latest server bits, because the embedded Mono has been removed (your settings opt into latest bits).

You should enable "omnisharp.useModernNet": true" instead to use the .NET 6 version rather than global Mono .