The C# language server has crashed. Restart extensions to re-enable C# functionality.

[jcleonis]

Type: Bug

Issue Description

Steps to Reproduce

Expected Behavior

Actual Behavior

Extension version: 2.133.5
VS Code version: Code 1.114.0 (e7fb5e96c0730b9deb70b33781f98e2f35975036, 2026-04-01T09:27:11Z)
OS version: Windows_NT x64 10.0.26200
Modes:

System Info

Item	Value
CPUs	AMD Ryzen 7 2700 Eight-Core Processor (16 x 3650)
GPU Status	2d_canvas: enabled GPU0: VENDOR= 0x1002, DEVICE=0x6fdf [AMD Radeon RX 580 2048SP], DRIVER_VENDOR=AMD, DRIVER_VERSION=31.0.21923.11000 ACTIVE GPU1: VENDOR= 0x1002, DEVICE=0x6fdf [AMD Radeon RX 580 2048SP], DRIVER_VERSION=31.0.21923.11000 GPU2: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.26100.8115 Machine model name: Machine model version: direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: disabled_off trees_in_viz: disabled_off video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	undefined
Memory (System)	31.93GB (10.78GB free)
Process Argv	--crash-reporter-id 38c11e0e-cad6-4cdb-9ddf-435e9542a8d1
Screen Reader	no
VM	50%

A/B Experiments

vsliv368cf:30146710
binariesv615:30325510
nativeloc1:31344060
dwcopilot:31170013
dwoutputs:31242946
copilot_t_ci:31333650
e5gg6876:31282496
pythonrdcb7:31342333
6518g693:31463988
aj953862:31281341
6abeh943:31336334
envsactivate1:31464700
cloudbuttont:31379625
aihoversummaries_f:31469309
3efgi100_wstrepl:31403338
use-responses-api:31390855
je187915:31454425
ec5jj548:31422691
cp_cls_c_966_ss:31454199
4je02754:31466945
8hhj4413:31478653
ge8j1254_inline_auto_hint_haiku:31488151
38bie571_auto:31426784
cp_cls_t_1081:31454832
ia-use-proxy-models-svc:31452481
e9c30283:31461165
test_treatment2:31471001
idci7584:31464702
nes-ftch-new:31485413
showingstats:31481873
534a6447:31478749
7ef87755:31458076
chat:31457767
8hig5102:31480529
67jbj424:31486320
t-some:31486549
cpptoolson-v2:31475363
db0gd219:31481871
23c7c724:31488001
ddid_t:31478206
getcmakediagnosticsoff:31487008
ja75b849:31488522

[dibarbet]

@jcleonis I suspect this might be a duplicate of #9130, but could you provide the 'C#' output window logs when you hit this crash? Thanks!

[matteorchard]

026-04-08 11:41:54.834 [error] [textDocument/didClose] [LSP] System.ArgumentException: Absolute path expected. (Parameter 'path')
   at Microsoft.CodeAnalysis.FileTextLoader..ctor(String path, Encoding defaultEncoding) in /_/src/Workspaces/Core/Portable/Workspace/Solution/FileTextLoader.cs:line 49
   at Microsoft.CodeAnalysis.Workspaces.ProjectSystem.ProjectSystemProjectFactory.CreateFileTextLoader(String fullPath) in /_/src/Workspaces/Core/Portable/Workspace/ProjectSystem/ProjectSystemProjectFactory.cs:line 98
   at Microsoft.CodeAnalysis.LanguageServer.HostWorkspace.LanguageServerWorkspace.<>c__DisplayClass11_0.<TryOnDocumentClosedAsync>b__0(Workspace w) in /_/src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/HostWorkspace/LanguageServerWorkspace.cs:line 126
   at Microsoft.CodeAnalysis.Workspaces.ProjectSystem.ProjectSystemProjectFactory.ApplyChangeToWorkspaceAsync(Action`1 action, CancellationToken cancellationToken)
   at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.<>c__DisplayClass11_1.<<StopTrackingAsync>b__1>d.MoveNext() in /_/src/LanguageServer/Protocol/Workspaces/LspWorkspaceManager.cs:line 189
--- End of stack trace from previous location ---
   at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.ApplyChangeToMutatingWorkspaceAsync(Workspace workspace, DocumentUri uri, Func`3 change) in /_/src/LanguageServer/Protocol/Workspaces/LspWorkspaceManager.cs:line 98
   at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.<>c__DisplayClass11_0.<<StopTrackingAsync>g__TryCloseDocumentsInMutatingWorkspaceAsync|0>d.MoveNext() in /_/src/LanguageServer/Protocol/Workspaces/LspWorkspaceManager.cs:line 180
--- End of stack trace from previous location ---
   at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.StopTrackingAsync(DocumentUri uri, CancellationToken cancellationToken) in /_/src/LanguageServer/Protocol/Workspaces/LspWorkspaceManager.cs:line 171
   at Microsoft.CodeAnalysis.LanguageServer.Handler.DocumentChanges.DidCloseHandler.HandleNotificationAsync(DidCloseTextDocumentParams request, RequestContext context, CancellationToken cancellationToken) in /_/src/LanguageServer/Protocol/Handler/DocumentChanges/DidCloseHandler.cs:line 32
   at Microsoft.CommonLanguageServerProtocol.Framework.QueueItem`1.StartRequestAsync[TRequest,TResponse](TRequest request, TRequestContext context, IMethodHandler handler, CancellationToken cancellationToken) in /_/src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework/QueueItem.cs:line 204
2026-04-08 11:41:54.835 [error] [LSP] System.ArgumentException: Absolute path expected. (Parameter 'path')
   at Microsoft.CodeAnalysis.FileTextLoader..ctor(String path, Encoding defaultEncoding) in /_/src/Workspaces/Core/Portable/Workspace/Solution/FileTextLoader.cs:line 49
   at Microsoft.CodeAnalysis.Workspaces.ProjectSystem.ProjectSystemProjectFactory.CreateFileTextLoader(String fullPath) in /_/src/Workspaces/Core/Portable/Workspace/ProjectSystem/ProjectSystemProjectFactory.cs:line 98
   at Microsoft.CodeAnalysis.LanguageServer.HostWorkspace.LanguageServerWorkspace.<>c__DisplayClass11_0.<TryOnDocumentClosedAsync>b__0(Workspace w) in /_/src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/HostWorkspace/LanguageServerWorkspace.cs:line 126
   at Microsoft.CodeAnalysis.Workspaces.ProjectSystem.ProjectSystemProjectFactory.ApplyChangeToWorkspaceAsync(Action`1 action, CancellationToken cancellationToken)
   at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.<>c__DisplayClass11_1.<<StopTrackingAsync>b__1>d.MoveNext() in /_/src/LanguageServer/Protocol/Workspaces/LspWorkspaceManager.cs:line 189
--- End of stack trace from previous location ---
   at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.ApplyChangeToMutatingWorkspaceAsync(Workspace workspace, DocumentUri uri, Func`3 change) in /_/src/LanguageServer/Protocol/Workspaces/LspWorkspaceManager.cs:line 98
   at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.<>c__DisplayClass11_0.<<StopTrackingAsync>g__TryCloseDocumentsInMutatingWorkspaceAsync|0>d.MoveNext() in /_/src/LanguageServer/Protocol/Workspaces/LspWorkspaceManager.cs:line 180
--- End of stack trace from previous location ---
   at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.StopTrackingAsync(DocumentUri uri, CancellationToken cancellationToken) in /_/src/LanguageServer/Protocol/Workspaces/LspWorkspaceManager.cs:line 171
   at Microsoft.CodeAnalysis.LanguageServer.Handler.DocumentChanges.DidCloseHandler.HandleNotificationAsync(DidCloseTextDocumentParams request, RequestContext context, CancellationToken cancellationToken) in /_/src/LanguageServer/Protocol/Handler/DocumentChanges/DidCloseHandler.cs:line 32
   at Microsoft.CommonLanguageServerProtocol.Framework.QueueItem`1.StartRequestAsync[TRequest,TResponse](TRequest request, TRequestContext context, IMethodHandler handler, CancellationToken cancellationToken) in /_/src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework/QueueItem.cs:line 204
   at Microsoft.CommonLanguageServerProtocol.Framework.QueueItem`1.StartRequestAsync[TRequest,TResponse](TRequest request, TRequestContext context, IMethodHandler handler, CancellationToken cancellationToken) in /_/src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework/QueueItem.cs:line 258
   at Microsoft.CodeAnalysis.LanguageServer.RoslynRequestExecutionQueue.WrapStartRequestTaskAsync(Task requestTask, Boolean rethrowExceptions) in /_/src/LanguageServer/Protocol/RoslynRequestExecutionQueue.cs:line 32
   at Microsoft.CommonLanguageServerProtocol.Framework.RequestExecutionQueue`1.ProcessQueueCoreAsync[TRequest,TResponse](QueueItem`1 work, IMethodHandler handler, RequestHandlerMetadata metadata, ConcurrentDictionary`2 concurrentlyExecutingTasks, CancellationTokenSource currentWorkCts, CancellationToken cancellationToken) in /_/src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework/RequestExecutionQueue.cs:line 372
   at Microsoft.CommonLanguageServerProtocol.Framework.RequestExecutionQueue`1.InvokeProcessCoreAsync(QueueItem`1 work, RequestHandlerMetadata metadata, IMethodHandler handler, MethodInfo methodInfo, ConcurrentDictionary`2 concurrentlyExecutingTasks, CancellationTokenSource currentWorkCts, CancellationToken cancellationToken) in /_/src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework/RequestExecutionQueue.cs:line 325
   at Microsoft.CommonLanguageServerProtocol.Framework.RequestExecutionQueue`1.ProcessQueueAsync() in /_/src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework/RequestExecutionQueue.cs:line 277
2026-04-08 11:41:54.837 [info] [LSP] Error occurred processing queue: Absolute path expected. (Parameter 'path').
2026-04-08 11:41:54.999 [info] Connection to server got closed. Server will restart.
2026-04-08 11:41:55.087 [error] Unhandled exception. System.ArgumentException: Absolute path expected. (Parameter 'path')
2026-04-08 11:41:55.087 [error]    at Microsoft.CodeAnalysis.FileTextLoader..ctor(String path, Encoding defaultEncoding) in /_/src/Workspaces/Core/Portable/Workspace/Solution/FileTextLoader.cs:line 49
2026-04-08 11:41:55.087 [error]    at Microsoft.CodeAnalysis.Workspaces.ProjectSystem.ProjectSystemProjectFactory.CreateFileTextLoader(String fullPath) in /_/src/Workspaces/Core/Portable/Workspace/ProjectSystem/ProjectSystemProjectFactory.cs:line 98
2026-04-08 11:41:55.087 [error]    at Microsoft.CodeAnalysis.LanguageServer.HostWorkspace.LanguageServerWorkspace.<>c__DisplayClass11_0.<TryOnDocumentClosedAsync>b__0(Workspace w) in /_/src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/HostWorkspace/LanguageServerWorkspace.cs:line 126
2026-04-08 11:41:55.087 [error]    at Microsoft.CodeAnalysis.Workspaces.ProjectSystem.ProjectSystemProjectFactory.ApplyChangeToWorkspaceAsync(Action`1 action, CancellationToken cancellationToken)
2026-04-08 11:41:55.087 [error]    at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.<>c__DisplayClass11_1.<<StopTrackingAsync>b__1>d.MoveNext() in /_/src/LanguageServer/Protocol/Workspaces/LspWorkspaceManager.cs:line 189
2026-04-08 11:41:55.087 [error] --- End of stack trace from previous location ---
2026-04-08 11:41:55.087 [error]    at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.ApplyChangeToMutatingWorkspaceAsync(Workspace workspace, DocumentUri uri, Func`3 change) in /_/src/LanguageServer/Protocol/Workspaces/LspWorkspaceManager.cs:line 98
2026-04-08 11:41:55.087 [error]    at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.<>c__DisplayClass11_0.<<StopTrackingAsync>g__TryCloseDocumentsInMutatingWorkspaceAsync|0>d.MoveNext() in /_/src/LanguageServer/Protocol/Workspaces/LspWorkspaceManager.cs:line 180
2026-04-08 11:41:55.087 [error] --- End of stack trace from previous location ---
2026-04-08 11:41:55.087 [error]    at Microsoft.CodeAnalysis.LanguageServer.LspWorkspaceManager.StopTrackingAsync(DocumentUri uri, CancellationToken cancellationToken) in /_/src/LanguageServer/Protocol/Workspaces/LspWorkspaceManager.cs:line 171
2026-04-08 11:41:55.087 [error]    at Microsoft.CodeAnalysis.LanguageServer.Handler.DocumentChanges.DidCloseHandler.HandleNotificationAsync(DidCloseTextDocumentParams request, RequestContext context, CancellationToken cancellationToken) in /_/src/LanguageServer/Protocol/Handler/DocumentChanges/DidCloseHandler.cs:line 32
2026-04-08 11:41:55.087 [error]    at Microsoft.CommonLanguageServerProtocol.Framework.QueueItem`1.StartRequestAsync[TRequest,TResponse](TRequest request, TRequestContext context, IMethodHandler handler, CancellationToken cancellationToken) in /_/src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework/QueueItem.cs:line 204
2026-04-08 11:41:55.087 [error]    at Microsoft.CommonLanguageServerProtocol.Framework.QueueItem`1.StartRequestAsync[TRequest,TResponse](TRequest request, TRequestContext context, IMethodHandler handler, CancellationToken cancellationToken) in /_/src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework/QueueItem.cs:line 258
2026-04-08 11:41:55.087 [error]    at Microsoft.CodeAnalysis.LanguageServer.RoslynRequestExecutionQueue.WrapStartRequestTaskAsync(Task requestTask, Boolean rethrowExceptions) in /_/src/LanguageServer/Protocol/RoslynRequestExecutionQueue.cs:line 32
2026-04-08 11:41:55.087 [error]    at Microsoft.CommonLanguageServerProtocol.Framework.RequestExecutionQueue`1.ProcessQueueCoreAsync[TRequest,TResponse](QueueItem`1 work, IMethodHandler handler, RequestHandlerMetadata metadata, ConcurrentDictionary`2 concurrentlyExecutingTasks, CancellationTokenSource currentWorkCts, CancellationToken cancellationToken) in /_/src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework/RequestExecutionQueue.cs:line 372
2026-04-08 11:41:55.087 [error]    at Microsoft.CommonLanguageServerProtocol.Framework.RequestExecutionQueue`1.InvokeProcessCoreAsync(QueueItem`1 work, RequestHandlerMetadata metadata, IMethodHandler handler, MethodInfo methodInfo, ConcurrentDictionary`2 concurrentlyExecutingTasks, CancellationTokenSource currentWorkCts, CancellationToken cancellationToken) in /_/src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework/RequestExecutionQueue.cs:line 325
2026-04-08 11:41:55.087 [error]    at Microsoft.CommonLanguageServerProtocol.Framework.RequestExecutionQueue`1.ProcessQueueAsync() in /_/src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework/RequestExecutionQueue.cs:line 277
2026-04-08 11:41:55.087 [error]    at Microsoft.CodeAnalysis.LanguageServer.LanguageServer.LanguageServerHost.WaitForExitAsync() in /_/src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/LanguageServer/LanguageServerHost.cs:line 78
2026-04-08 11:41:55.087 [error]    at Program.<<Main>$>g__RunAsync|0_0(ServerConfiguration serverConfiguration, CancellationToken cancellationToken) in /_/src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/Program.cs:line 153
2026-04-08 11:41:55.087 [error]    at Program.<<Main>$>g__RunAsync|0_0(ServerConfiguration serverConfiguration, CancellationToken cancellationToken) in /_/src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/Program.cs:line 161
2026-04-08 11:41:55.087 [error]    at System.CommandLine.Command.<>c__DisplayClass32_0.<<SetAction>b__0>d.MoveNext()
2026-04-08 11:41:55.087 [error] --- End of stack trace from previous location ---
2026-04-08 11:41:55.087 [error]    at System.CommandLine.Invocation.InvocationPipeline.InvokeAsync(ParseResult parseResult, CancellationToken cancellationToken)
2026-04-08 11:41:55.087 [error]    at Program.<Main>$(String[] args) in /_/src/LanguageServer/Microsoft.CodeAnalysis.LanguageServer/Program.cs:line 32
2026-04-08 11:41:55.087 [error]    at Program.<Main>(String[] args)
2026-04-08 11:41:57.880 [info] info: Program[0]
2026-04-08 11:41:57.880 [info]       Server started with process ID 50960
2026-04-08 11:42:04.234 [info] [Program] Language server initialized
2026-04-08 11:42:04.238 [info] [Program] Monitoring client process 45916 for exit
2026-04-08 11:42:50.497 [error] Server process exited with code 3762504530.

vscode output window

[dibarbet]

@matteorchard I think this issue may have been fixed the latest prerelease (v2.134.7), if you wouldn't mind trying it out. Let me know if not. Thanks!