C# extension is broken after cursor 1.6.2 version

10ppa · September 10, 2025, 1:51pm

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

getting this error:

2025-09-10 09:36:26.964 [info] [Error - 9:36:26 AM] [solution/open] [LanguageServerHost] System.IO.FileNotFoundException: 
File name: 'System.Diagnostics.Process, Version=9.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
   at Microsoft.CodeAnalysis.MSBuild.BuildHostProcessManager.GetBuildHostAsync(BuildHostProcessKind buildHostKind, CancellationToken cancellationToken)
   at System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start[TStateMachine](TStateMachine& stateMachine)
   at Microsoft.CodeAnalysis.MSBuild.BuildHostProcessManager.GetBuildHostAsync(BuildHostProcessKind buildHostKind, CancellationToken cancellationToken)
   at Microsoft.CodeAnalysis.LanguageServer.HostWorkspace.LanguageServerProjectSystem.OpenSolutionAsync(String solutionFilePath)
   at Microsoft.CodeAnalysis.LanguageServer.HostWorkspace.LanguageServerProjectSystem.OpenSolutionAsync(String solutionFilePath)
   at Microsoft.CommonLanguageServerProtocol.Framework.QueueItem`1.StartRequestAsync[TRequest,TResponse](TRequest request, TRequestContext context, IMethodHandler handler, String language, CancellationToken cancellationToken)
2025-09-10 09:36:27.087 [info] [Error - 9:36:27 AM] [LanguageServerHost] System.TypeInitializationException: The type initializer for 'Microsoft.CodeAnalysis.CodeStyle.NamingStyleOptions' threw an exception.
 ---> System.TypeInitializationException: The type initializer for 'Microsoft.CodeAnalysis.Diagnostics.Analyzers.NamingStyles.NamingStylePreferences' threw an exception.
 ---> System.IO.FileNotFoundException: 
File name: 'System.Private.Xml, Version=9.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'
   at Microsoft.CodeAnalysis.Diagnostics.Analyzers.NamingStyles.NamingStylePreferences..cctor()
   --- End of inner exception stack trace ---
   at Microsoft.CodeAnalysis.CodeStyle.NamingStyleOptions..cctor()
   --- End of inner exception stack trace ---
   at Microsoft.CodeAnalysis.Options.EditorConfigOptionsEnumerator.GetLanguageAgnosticEditorConfigOptions(Boolean includeUnsupported)+MoveNext()
   at Microsoft.CodeAnalysis.CSharp.Options.CSharpEditorConfigOptionsEnumerator.GetOptions(Boolean includeUnsupported)+MoveNext()
   at System.Linq.Enumerable.SelectManySingleSelectorIterator`2.MoveNext()
   at Microsoft.CodeAnalysis.Options.ClientFallbackAnalyzerConfigOptionsProvider.GetOptions(String language)
   at Microsoft.CodeAnalysis.Workspace.InitializeAnalyzerFallbackOptions(Solution oldSolution, Solution newSolution)
   at Microsoft.CodeAnalysis.Workspace.<>c.<SetCurrentSolutionAsync>b__30_3(Solution oldSolution, ValueTuple`5 data)
   at Microsoft.CodeAnalysis.Workspace.SetCurrentSolutionAsync[TData](Boolean useAsync, TData data, Func`3 transformation, Boolean mayRaiseEvents, Action`3 onBeforeUpdate, Action`3 onAfterUpdate, CancellationToken cancellationToken)
   at Microsoft.CodeAnalysis.Workspace.SetCurrentSolutionAsync(Boolean useAsync, Func`2 transformation, Func`3 changeKind, Action`2 onBeforeUpdate, Action`2 onAfterUpdate, CancellationToken cancellationToken)
   at Roslyn.Utilities.ValueTaskExtensions.VerifyCompleted[T](ValueTask`1 task, String message)
   at Microsoft.CodeAnalysis.Workspace.SetCurrentSolution(Func`2 transformation, WorkspaceChangeKind changeKind, ProjectId projectId, DocumentId documentId, Action`2 onBeforeUpdate, Action`2 onAfterUpdate)
   at Microsoft.CodeAnalysis.Workspace.OnProjectAdded(ProjectInfo projectInfo)
   at Microsoft.CodeAnalysis.LanguageServer.LspMiscellaneousFilesWorkspace.AddMiscellaneousDocument(Uri uri, SourceText documentText, String languageId, ILspLogger logger)
   at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.GetLspDocumentInfoAsync(TextDocumentIdentifier textDocumentIdentifier, CancellationToken cancellationToken)
   at Microsoft.CodeAnalysis.LanguageServer.Handler.RequestContext.CreateAsync(Boolean mutatesSolutionState, Boolean requiresLSPSolution, TextDocumentIdentifier textDocument, WellKnownLspServerKinds serverKind, ClientCapabilities clientCapabilities, ImmutableArray`1 supportedLanguages, ILspServices lspServices, ILspLogger logger, String method, CancellationToken cancellationToken)
   at Microsoft.CommonLanguageServerProtocol.Framework.QueueItem`1.CreateRequestContextAsync[TRequest](IMethodHandler handler, RequestHandlerMetadata requestHandlerMetadata, AbstractLanguageServer`1 languageServer, CancellationToken cancellationToken)
   at Microsoft.CommonLanguageServerProtocol.Framework.RequestExecutionQueue`1.ProcessQueueCoreAsync[TRequest,TResponse](IQueueItem`1 work, IMethodHandler handler, RequestHandlerMetadata metadata, ConcurrentDictionary`2 concurrentlyExecutingTasks, CancellationTokenSource currentWorkCts, CancellationToken cancellationToken)
   at Microsoft.CommonLanguageServerProtocol.Framework.RequestExecutionQueue`1.InvokeProcessCoreAsync(IQueueItem`1 work, RequestHandlerMetadata metadata, IMethodHandler handler, MethodInfo methodInfo, ConcurrentDictionary`2 concurrentlyExecutingTasks, CancellationTokenSource currentWorkCts, CancellationToken cancellationToken)
   at Microsoft.CommonLanguageServerProtocol.Framework.RequestExecutionQueue`1.ProcessQueueAsync()
2025-09-10 09:36:27.088 [info] [Info  - 9:36:27 AM] Error processing queue, shutting down
2025-09-10 09:36:27.089 [info] [Error - 9:36:27 AM] Workspace diagnostic pull failed.
2025-09-10 09:36:27.089 [info] Canceled: Canceled
	at l4.handleFailedRequest (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:89:9256)
	at l4.handleFailedRequest (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:1227:870)
	at c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:83:12419
	at runNextTicks (node:internal/process/task_queues:60:5)
	at process.processImmediate (node:internal/timers:454:9)
	at process.topLevelDomainCallback (node:domain:161:15)
	at process.callbackTrampoline (node:internal/async_hooks:128:24)
	at async Object.z$ [as provideWorkspaceDiagnostics] (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:1221:5524)
	at async kJ.pullWorkspaceAsync (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:83:9721)
2025-09-10 09:36:27.094 [info] [Error - 9:36:27 AM] Client Microsoft.CodeAnalysis.LanguageServer: connection to server is erroring.
write EOF
Shutting down server.
2025-09-10 09:36:27.094 [info] [Error - 9:36:27 AM] Client Microsoft.CodeAnalysis.LanguageServer: connection to server is erroring.
write EOF
Shutting down server.
2025-09-10 09:36:27.094 [info] [Error - 9:36:27 AM] Client Microsoft.CodeAnalysis.LanguageServer: connection to server is erroring.
write EOF
2025-09-10 09:36:27.094 [info] [Error - 9:36:27 AM] Request textDocument/diagnostic failed.
2025-09-10 09:36:27.094 [info]   Message: write EOF
  Code: -32099 
2025-09-10 09:36:27.094 [info] [Error - 9:36:27 AM] Document pull failed for text document file:///d%3A/work/projects/DOT.Service/src/ApiServer/Controllers/JobsController.cs
2025-09-10 09:36:27.094 [info]   Message: write EOF
  Code: -32099 
2025-09-10 09:36:27.095 [info] [Error - 9:36:27 AM] Client Microsoft.CodeAnalysis.LanguageServer: connection to server is erroring.
Cannot call write after a stream was destroyed
2025-09-10 09:36:27.095 [info] [Error - 9:36:27 AM] Request textDocument/diagnostic failed.
2025-09-10 09:36:27.095 [info]   Message: Cannot call write after a stream was destroyed
  Code: -32099 
2025-09-10 09:36:27.095 [info] [Error - 9:36:27 AM] Document pull failed for text document file:///d%3A/work/work/projects/DOT.Service/src/ApiServer/Controllers/JobsController.cs
2025-09-10 09:36:27.095 [info]   Message: Cannot call write after a stream was destroyed
  Code: -32099 
2025-09-10 09:36:27.096 [info] [Error - 9:36:27 AM] Connection to server got closed. Server will not be restarted.
2025-09-10 09:36:27.096 [info] [Error - 9:36:27 AM] Stopping server failed
2025-09-10 09:36:27.096 [info]   Message: Pending response rejected since connection got disposed
  Code: -32097 
2025-09-10 09:36:27.097 [info] [Error - 9:36:27 AM] Stopping server failed
2025-09-10 09:36:27.097 [info]   Message: Pending response rejected since connection got disposed
  Code: -32097 
2025-09-10 09:36:27.097 [info] [Error - 9:36:27 AM] Stopping server failed
2025-09-10 09:36:27.097 [info]   Message: Pending response rejected since connection got disposed
  Code: -32097

Steps to Reproduce

Open a dotnet solution that is part of a workspace folder

Expected Behavior

load all C# symbols and allow to navigate C# code

Operating System

Windows 10/11

Current Cursor Version (Menu → About Cursor → Copy)

Version: 1.6.2 (user setup)
VSCode Version: 1.99.3
Commit: bd5fd93a09094d25439613994246c5b892c18180
Date: 2025-09-09T20:24:24.139Z
Electron: 34.5.8
Chromium: 132.0.6834.210
Node.js: 20.19.1
V8: 13.2.152.41-electron.0
OS: Windows_NT x64 10.0.26220

Does this stop you from using Cursor

No - Cursor works, but with this issue

deanrie · September 10, 2025, 1:55pm

Hey, are you using the official extension from Microsoft or ours?

10ppa · September 10, 2025, 1:57pm

Anysphere one, I think the MS one is not workable at all

10ppa · September 10, 2025, 2:15pm

when I open the workspace I first get this error:

ms-dotnettools.csharp requested to download the .NET Runtime.

Downloading .NET version(s) 9.0.9\~x64 ...

Could not find the architecture of the dotnet host c:\\Users\\ddiep\\AppData\\Roaming\\Cursor\\User\\globalStorage\\ms-dotnettools.vscode-dotnet-runtime\\.dotnet\\9.0.9\~x64\\dotnet.exe. If this host does not match the architecture x64:

Please set the PATH to a dotnet host that matches the architecture x64. An incorrect architecture will cause instability for the extension ms-dotnettools.csharp.

..... Done!

.NET 9.0.9\~x64 executable path: c:\\Users\\ddiep\\AppData\\Roaming\\Cursor\\User\\globalStorage\\ms-dotnettools.vscode-dotnet-runtime\\.dotnet\\9.0.9\~x64\\dotnet.exe

then the C# extension start failing. This is the entire Log in the console output:

2025-09-10 10:02:08.923 [info] Locating .NET runtime version 9.0.1
2025-09-10 10:02:15.234 [info] Did not find .NET 9.0.1 on path, falling back to acquire runtime via ms-dotnettools.vscode-dotnet-runtime
2025-09-10 10:02:23.813 [info] Dotnet path: c:\Users\ddiep\AppData\Roaming\Cursor\User\globalStorage\ms-dotnettools.vscode-dotnet-runtime\.dotnet\9.0.9~x64\dotnet.exe
2025-09-10 10:02:23.813 [info] Activating C# standalone...
2025-09-10 10:02:24.525 [info] [stdout] {"pipeName":"\\\\.\\pipe\\ab7c2c0b"}

2025-09-10 10:02:24.525 [info] received named pipe information from server
2025-09-10 10:02:24.526 [info] client has connected to server
2025-09-10 10:02:24.594 [info] [Info  - 10:02:24 AM] [Program] Language server initialized
2025-09-10 10:02:24.920 [info] [Info  - 10:02:24 AM] [solution/open] [LanguageServerProjectSystem] Loading d:\work\CAMS.Service\CAMS.Service.sln...
2025-09-10 10:02:24.922 [info] [Error - 10:02:24 AM] [solution/open] [LanguageServerHost] System.IO.FileNotFoundException: 
File name: 'System.Diagnostics.Process, Version=9.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'
   at Microsoft.CodeAnalysis.MSBuild.BuildHostProcessManager.GetBuildHostAsync(BuildHostProcessKind buildHostKind, CancellationToken cancellationToken)
   at System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start[TStateMachine](TStateMachine& stateMachine)
   at Microsoft.CodeAnalysis.MSBuild.BuildHostProcessManager.GetBuildHostAsync(BuildHostProcessKind buildHostKind, CancellationToken cancellationToken)
   at Microsoft.CodeAnalysis.LanguageServer.HostWorkspace.LanguageServerProjectSystem.OpenSolutionAsync(String solutionFilePath)
   at Microsoft.CodeAnalysis.LanguageServer.HostWorkspace.LanguageServerProjectSystem.OpenSolutionAsync(String solutionFilePath)
   at Microsoft.CommonLanguageServerProtocol.Framework.QueueItem`1.StartRequestAsync[TRequest,TResponse](TRequest request, TRequestContext context, IMethodHandler handler, String language, CancellationToken cancellationToken)
2025-09-10 10:02:25.023 [info] [Error - 10:02:25 AM] [LanguageServerHost] System.TypeInitializationException: The type initializer for 'Microsoft.CodeAnalysis.CodeStyle.NamingStyleOptions' threw an exception.
 ---> System.TypeInitializationException: The type initializer for 'Microsoft.CodeAnalysis.Diagnostics.Analyzers.NamingStyles.NamingStylePreferences' threw an exception.
 ---> System.IO.FileNotFoundException: 
File name: 'System.Private.Xml.Linq, Version=9.0.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51'
   at Microsoft.CodeAnalysis.Diagnostics.Analyzers.NamingStyles.NamingStylePreferences..cctor()
   --- End of inner exception stack trace ---
   at Microsoft.CodeAnalysis.CodeStyle.NamingStyleOptions..cctor()
   --- End of inner exception stack trace ---
   at Microsoft.CodeAnalysis.Options.EditorConfigOptionsEnumerator.GetLanguageAgnosticEditorConfigOptions(Boolean includeUnsupported)+MoveNext()
   at Microsoft.CodeAnalysis.CSharp.Options.CSharpEditorConfigOptionsEnumerator.GetOptions(Boolean includeUnsupported)+MoveNext()
   at System.Linq.Enumerable.SelectManySingleSelectorIterator`2.MoveNext()
   at Microsoft.CodeAnalysis.Options.ClientFallbackAnalyzerConfigOptionsProvider.GetOptions(String language)
   at Microsoft.CodeAnalysis.Workspace.InitializeAnalyzerFallbackOptions(Solution oldSolution, Solution newSolution)
   at Microsoft.CodeAnalysis.Workspace.<>c.<SetCurrentSolutionAsync>b__30_3(Solution oldSolution, ValueTuple`5 data)
   at Microsoft.CodeAnalysis.Workspace.SetCurrentSolutionAsync[TData](Boolean useAsync, TData data, Func`3 transformation, Boolean mayRaiseEvents, Action`3 onBeforeUpdate, Action`3 onAfterUpdate, CancellationToken cancellationToken)
   at Microsoft.CodeAnalysis.Workspace.SetCurrentSolutionAsync(Boolean useAsync, Func`2 transformation, Func`3 changeKind, Action`2 onBeforeUpdate, Action`2 onAfterUpdate, CancellationToken cancellationToken)
   at Roslyn.Utilities.ValueTaskExtensions.VerifyCompleted[T](ValueTask`1 task, String message)
   at Microsoft.CodeAnalysis.Workspace.SetCurrentSolution(Func`2 transformation, WorkspaceChangeKind changeKind, ProjectId projectId, DocumentId documentId, Action`2 onBeforeUpdate, Action`2 onAfterUpdate)
   at Microsoft.CodeAnalysis.Workspace.OnProjectAdded(ProjectInfo projectInfo)
   at Microsoft.CodeAnalysis.LanguageServer.LspMiscellaneousFilesWorkspace.AddMiscellaneousDocument(Uri uri, SourceText documentText, String languageId, ILspLogger logger)
   at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.GetLspDocumentInfoAsync(TextDocumentIdentifier textDocumentIdentifier, CancellationToken cancellationToken)
   at Microsoft.CodeAnalysis.LanguageServer.Handler.RequestContext.CreateAsync(Boolean mutatesSolutionState, Boolean requiresLSPSolution, TextDocumentIdentifier textDocument, WellKnownLspServerKinds serverKind, ClientCapabilities clientCapabilities, ImmutableArray`1 supportedLanguages, ILspServices lspServices, ILspLogger logger, String method, CancellationToken cancellationToken)
   at Microsoft.CommonLanguageServerProtocol.Framework.QueueItem`1.CreateRequestContextAsync[TRequest](IMethodHandler handler, RequestHandlerMetadata requestHandlerMetadata, AbstractLanguageServer`1 languageServer, CancellationToken cancellationToken)
   at Microsoft.CommonLanguageServerProtocol.Framework.RequestExecutionQueue`1.ProcessQueueCoreAsync[TRequest,TResponse](IQueueItem`1 work, IMethodHandler handler, RequestHandlerMetadata metadata, ConcurrentDictionary`2 concurrentlyExecutingTasks, CancellationTokenSource currentWorkCts, CancellationToken cancellationToken)
   at Microsoft.CommonLanguageServerProtocol.Framework.RequestExecutionQueue`1.InvokeProcessCoreAsync(IQueueItem`1 work, RequestHandlerMetadata metadata, IMethodHandler handler, MethodInfo methodInfo, ConcurrentDictionary`2 concurrentlyExecutingTasks, CancellationTokenSource currentWorkCts, CancellationToken cancellationToken)
   at Microsoft.CommonLanguageServerProtocol.Framework.RequestExecutionQueue`1.ProcessQueueAsync()
2025-09-10 10:02:25.024 [info] [Info  - 10:02:25 AM] Error processing queue, shutting down
2025-09-10 10:02:25.026 [info] [Error - 10:02:25 AM] Workspace diagnostic pull failed.
2025-09-10 10:02:25.026 [info] Canceled: Canceled
	at l4.handleFailedRequest (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:89:9256)
	at l4.handleFailedRequest (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:1227:870)
	at c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:83:12419
	at runNextTicks (node:internal/process/task_queues:60:5)
	at process.processImmediate (node:internal/timers:454:9)
	at process.topLevelDomainCallback (node:domain:161:15)
	at process.callbackTrampoline (node:internal/async_hooks:128:24)
	at async Object.z$ [as provideWorkspaceDiagnostics] (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:1221:5524)
	at async kJ.pullWorkspaceAsync (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:83:9721)
2025-09-10 10:02:25.027 [info] [Error - 10:02:25 AM] Workspace diagnostic pull failed.
2025-09-10 10:02:25.027 [info] Canceled: Canceled
	at l4.handleFailedRequest (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:89:9256)
	at l4.handleFailedRequest (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:1227:870)
	at c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:83:12419
	at runNextTicks (node:internal/process/task_queues:60:5)
	at process.processImmediate (node:internal/timers:454:9)
	at process.topLevelDomainCallback (node:domain:161:15)
	at process.callbackTrampoline (node:internal/async_hooks:128:24)
	at async Object.z$ [as provideWorkspaceDiagnostics] (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:1221:5524)
	at async kJ.pullWorkspaceAsync (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:83:9721)
2025-09-10 10:02:25.028 [info] [Error - 10:02:25 AM] Client Microsoft.CodeAnalysis.LanguageServer: connection to server is erroring.
This socket has been ended by the other party
2025-09-10 10:02:25.029 [info] [Error - 10:02:25 AM] Request textDocument/diagnostic failed.
2025-09-10 10:02:25.029 [info]   Message: This socket has been ended by the other party
  Code: -32099 
2025-09-10 10:02:25.029 [info] [Error - 10:02:25 AM] Document pull failed for text document file:///d%3A/work/CAMS.Service/src/ApiServer/Controllers/JobsController.cs
2025-09-10 10:02:25.029 [info]   Message: This socket has been ended by the other party
  Code: -32099 
2025-09-10 10:02:25.034 [info] [Info  - 10:02:25 AM] Connection to server got closed. Server will restart.
2025-09-10 10:02:25.036 [info] Dotnet path: c:\Users\ddiep\AppData\Roaming\Cursor\User\globalStorage\ms-dotnettools.vscode-dotnet-runtime\.dotnet\9.0.9~x64\dotnet.exe
2025-09-10 10:02:25.036 [info] Activating C# standalone...
2025-09-10 10:02:25.060 [info] Language server process exited with 0
2025-09-10 10:02:25.089 [error] [stderr] You must install or update .NET to run this application.

App: C:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\.roslyn\Microsoft.CodeAnalysis.LanguageServer.exe
Architecture: x64

2025-09-10 10:02:25.089 [error] [stderr] Framework: 'Microsoft.NETCore.App', version '9.0.0' (x64)
.NET location: c:\Users\ddiep\AppData\Roaming\Cursor\User\globalStorage\ms-dotnettools.vscode-dotnet-runtime\.dotnet\9.0.9~x64

No frameworks were found.

Learn more:
https://aka.ms/dotnet/app-launch-failed

To install missing framework, download:
https://aka.ms/dotnet-core-applaunch?framework=Microsoft.NETCore.App&framework_version=9.0.0&arch=x64&rid=win-x64&os=win10

2025-09-10 10:02:25.094 [info] Language server process exited with 2147516566
2025-09-10 10:02:25.095 [info] [Error - 10:02:25 AM] Microsoft.CodeAnalysis.LanguageServer client: couldn't create connection to server.
2025-09-10 10:02:25.095 [info] Error: Language server process exited unexpectedly
	at ChildProcess.<anonymous> (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:1227:20302)
	at ChildProcess.emit (node:events:536:35)
	at ChildProcess.emit (node:domain:489:12)
	at ChildProcess._handle.onexit (node:internal/child_process:293:12)
	at Process.callbackTrampoline (node:internal/async_hooks:130:17)
2025-09-10 10:02:25.095 [info] [Error - 10:02:25 AM] Restarting server failed
2025-09-10 10:02:25.095 [info] Error: Language server process exited unexpectedly
	at ChildProcess.<anonymous> (c:\Users\ddiep\.cursor\extensions\anysphere.csharp-1.0.1-win32-x64\dist\extension.js:1227:20302)
	at ChildProcess.emit (node:events:536:35)
	at ChildProcess.emit (node:domain:489:12)
	at ChildProcess._handle.onexit (node:internal/child_process:293:12)
	at Process.callbackTrampoline (node:internal/async_hooks:130:17)

ravirahman · September 10, 2025, 4:17pm

Hi @10ppa, if the framework failed to install, you might need to download it manually:

In the logs I see:

No frameworks were found.

Learn more:
https://aka.ms/dotnet/app-launch-failed

To install missing framework, download:
https://aka.ms/dotnet-core-applaunch?framework=Microsoft.NETCore.App&framework_version=9.0.0&arch=x64&rid=win-x64&os=win10

10ppa · September 10, 2025, 5:49pm

but why to download any framework? it was working yesterday, this started to happen after the last version of Cursor was installed today in the morning. I have being working in the same project for months in Cursor and never got this error.

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