error on automatic format for .cshtml file

[NEOSDEVNIC]

Type: Bug

Issue Description

Save changes in a .cshtml

Steps to Reproduce

modify a cshtml file with copilot

Expected Behavior

save with out fails

Actual Behavior

save changes but notify than automatic format fails

Extension version: 2.140.8
VS Code version: Code - Insiders 1.122.0-insider (6bb5e61adc5714fd0313615ea510be49b5fdd5f1, 2026-05-28T14:33:59+10:00)
OS version: Windows_NT x64 10.0.26200
Modes:

Logs

C# log

Details

2026-05-28 06:00:16.275 [info] Locating .NET runtime version 10.0.5
2026-05-28 06:00:16.865 [info] Dotnet path: C:\Program Files\dotnet\dotnet.exe
2026-05-28 06:00:16.865 [info] Activating C# + C# Dev Kit...
2026-05-28 06:00:17.668 [info] info: Program[0]
2026-05-28 06:00:17.668 [info]       Server started with process ID 13556
2026-05-28 06:00:19.422 [info] [Program] Language server initialized
2026-05-28 06:00:19.425 [info] [Program] Monitoring client process 14508 for exit
2026-05-28 06:00:19.954 [info] [initialized] [Microsoft.CodeAnalysis.LanguageServer.FileBasedPrograms.FileBasedProgramsEntryPointDiscovery] Finished discovery in 'd:\peopleapps\SISRUAP_FE\SRP.UI' in 15 milliseconds
2026-05-28 06:00:21.702 [info] [textDocument/_vs_getProjectContexts] [Microsoft.CodeAnalysis.MSBuild.BuildHostProcessManager] .NET BuildHost started from c:\Users\Jose L Moreno\.vscode-insiders\extensions\ms-dotnettools.csharp-2.140.8-win32-x64\.roslyn\Microsoft.CodeAnalysis.LanguageServer.exe reloading to start from C:\Program Files\dotnet\dotnet.exe to match necessary SDK location.
2026-05-28 06:00:23.865 [warning] [textDocument/_vs_getProjectContexts] [LanguageServerProjectLoader] Project C:\Users\Jose L Moreno\AppData\Local\Temp\roslyn-canonical-misc\7b969449-4f6c-4228-a793-d0b5aa41890c\Canonical.csproj has unresolved dependencies
2026-05-28 06:00:25.391 [info] [serviceBroker/connect] [WorkspaceProjectFactoryService] Project D:\peopleapps\SISRUAP_FE\SRP.UI\SRP.UI.csproj loaded by C# Dev Kit
2026-05-28 06:00:31.617 [info] [textDocument/_vs_getProjectContexts] [LanguageServerProjectLoader] Successfully completed load of d:\peopleapps\SISRUAP_FE\SRP.UI\Controllers\FOMUJERES\EmpoderamientoController.cs
2026-05-28 06:00:31.633 [info] [textDocument/_vs_getProjectContexts] [LanguageServerProjectLoader] Restoring Canonical.csproj: Running dotnet restore on C:\Users\Jose L Moreno\AppData\Local\Temp\roslyn-canonical-misc\7b969449-4f6c-4228-a793-d0b5aa41890c\Canonical.csproj
2026-05-28 06:00:31.634 [info] [textDocument/_vs_getProjectContexts] [Microsoft.CodeAnalysis.LanguageServer.DotnetCliHelper] Using dotnet executable configured on the PATH
2026-05-28 06:00:32.636 [info] [textDocument/_vs_getProjectContexts] [LanguageServerProjectLoader] Restoring Canonical.csproj:   Determining projects to restore...
2026-05-28 06:00:32.991 [info] [textDocument/_vs_getProjectContexts] [LanguageServerProjectLoader] Restoring Canonical.csproj:   Restored C:\Users\Jose L Moreno\AppData\Local\Temp\roslyn-canonical-misc\7b969449-4f6c-4228-a793-d0b5aa41890c\Canonical.csproj (in 89 ms).
2026-05-28 06:00:33.058 [info] [textDocument/_vs_getProjectContexts] [LanguageServerProjectLoader] Restore complete
2026-05-28 06:00:33.058 [info] [textDocument/_vs_getProjectContexts] [LanguageServerProjectLoader] Completed (re)load of all projects in 00:00:12.5740264
2026-05-28 06:00:46.914 [info] [workspace/didChangeWatchedFiles] [LanguageServerProjectLoader] Completed (re)load of all projects in 00:00:00.0012539
2026-05-28 06:52:44.712 [error] Request textDocument/formatting failed.
  Message: 'end' must not be less than 'start'. start='6933' end='6908'. (Parameter 'end')
  Code: -32000 
[object Object]
2026-05-28 06:59:04.527 [error] Request textDocument/formatting failed.
  Message: 'end' must not be less than 'start'. start='6933' end='6908'. (Parameter 'end')
  Code: -32000 
[object Object]
2026-05-28 06:59:20.579 [error] Request textDocument/formatting failed.
  Message: 'end' must not be less than 'start'. start='6933' end='6908'. (Parameter 'end')
  Code: -32000 
[object Object]
2026-05-28 06:59:34.093 [error] Request textDocument/formatting failed.
  Message: 'end' must not be less than 'start'. start='6933' end='6908'. (Parameter 'end')
  Code: -32000 
[object Object]

C# LSP Trace Logs log

Details

Environment Information

VSCode version: 1.122.0-insider
C# Extension: 2.140.8
Using OmniSharp: false

Dotnet Information

.NET SDK: Version: 10.0.300 Commit: caa81fa497 Workload version: 10.0.300-manifests.e0989437 MSBuild version: 18.6.3+caa81fa49

Runtime Environment:
OS Name: Windows
OS Version: 10.0.26200
OS Platform: Windows
RID: win-x64
Base Path: C:\Program Files\dotnet\sdk\10.0.300\

.NET workloads installed:
[wasm-tools]
Installation Source: VS 17.14.37314.3, VS 18.7.11819.209
Manifest Version: 10.0.108/10.0.100
Manifest Path: C:\Program Files\dotnet\sdk-manifests\10.0.100\microsoft.net.workload.mono.toolchain.current\10.0.108\WorkloadManifest.json
Install Type: Msi

Configured to use workload sets when installing new manifests.
No workload sets are installed. Run "dotnet workload restore" to install a workload set.

Host:
Version: 10.0.8
Architecture: x64
Commit: 94ea82652c

.NET SDKs installed:
6.0.428 [C:\Program Files\dotnet\sdk]
9.0.100-rc.2.24474.11 [C:\Program Files\dotnet\sdk]
9.0.200 [C:\Program Files\dotnet\sdk]
9.0.314 [C:\Program Files\dotnet\sdk]
10.0.300 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
Microsoft.AspNetCore.App 3.1.32 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 6.0.36 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 7.0.20 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 8.0.27 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 9.0.0-rc.2.24474.3 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 9.0.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 9.0.16 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 10.0.8 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 3.1.32 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 6.0.36 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 7.0.20 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 8.0.27 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.0-rc.2.24473.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.16 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 10.0.8 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 3.1.32 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 6.0.36 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 7.0.20 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 8.0.27 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 9.0.0-rc.2.24474.4 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 9.0.2 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 9.0.16 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 10.0.8 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

Other architectures found:
x86 [C:\Program Files (x86)\dotnet]
registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\x86\InstallLocation]

Environment variables:
DOTNET_CLI_UI_LANGUAGE [en-US]

global.json file:
Not found

Learn more:
https://aka.ms/dotnet/info

Download .NET:
https://aka.ms/dotnet/download

Visual Studio Code Extensions

Extension	Author	Version	Folder Name
azurite	Azurite	3.35.0	azurite.azurite-3.35.0
better-comments	aaron-bond	3.0.2	aaron-bond.better-comments-3.0.2
continue	Continue	1.3.38	continue.continue-1.3.38-win32-x64
csdevkit	ms-dotnettools	3.20.199	ms-dotnettools.csdevkit-3.20.199-win32-x64
csharp	ms-dotnettools	2.140.8	ms-dotnettools.csharp-2.140.8-win32-x64
data-workspace-vscode	ms-mssql	0.6.3	ms-mssql.data-workspace-vscode-0.6.3
debugpy	ms-python	2026.7.11471010	ms-python.debugpy-2026.7.11471010-win32-x64
docstring	Docstring	0.6.3	docstring.docstring-0.6.3
jupyter	ms-toolsai	2025.9.1	ms-toolsai.jupyter-2025.9.1-win32-x64
jupyter-keymap	ms-toolsai	1.1.2	ms-toolsai.jupyter-keymap-1.1.2
jupyter-renderers	ms-toolsai	1.3.2025062701	ms-toolsai.jupyter-renderers-1.3.2025062701
MagicPython	magicstack	1.1.0	magicstack.magicpython-1.1.0
material-icon-theme	PKief	5.35.0	pkief.material-icon-theme-5.35.0
mingit	muhammadmohsen	0.12.4	muhammadmohsen.mingit-0.12.4
monotainer	monosyde	0.1.4	monosyde.monotainer-0.1.4
mssql	ms-mssql	1.42.2	ms-mssql.mssql-1.42.2
ng-template	Angular	21.2.4	angular.ng-template-21.2.4
notepadplusplus-keybindings	ms-vscode	1.0.7	ms-vscode.notepadplusplus-keybindings-1.0.7
python	ms-python	2026.5.2026052501	ms-python.python-2026.5.2026052501-win32-x64
remote-containers	ms-vscode-remote	0.460.0	ms-vscode-remote.remote-containers-0.460.0
sql-bindings-vscode	ms-mssql	0.4.1	ms-mssql.sql-bindings-vscode-0.4.1
sql-database-projects-vscode	ms-mssql	1.5.9	ms-mssql.sql-database-projects-vscode-1.5.9
vscode-azureappservice	ms-azuretools	0.26.5	ms-azuretools.vscode-azureappservice-0.26.5
vscode-azureresourcegroups	ms-azuretools	0.12.4	ms-azuretools.vscode-azureresourcegroups-0.12.4
vscode-containers	ms-azuretools	2.4.4	ms-azuretools.vscode-containers-2.4.4
vscode-database-client2	cweijan	8.4.7	cweijan.vscode-database-client2-8.4.7
vscode-docker-registry-explorer	TqrHsn	0.1.3	tqrhsn.vscode-docker-registry-explorer-0.1.3
vscode-dotnet-runtime	ms-dotnettools	3.0.2	ms-dotnettools.vscode-dotnet-runtime-3.0.2
vscode-jupyter-cell-tags	ms-toolsai	0.1.9	ms-toolsai.vscode-jupyter-cell-tags-0.1.9
vscode-jupyter-powertoys	ms-toolsai	0.1.1	ms-toolsai.vscode-jupyter-powertoys-0.1.1
vscode-jupyter-slideshow	ms-toolsai	0.1.6	ms-toolsai.vscode-jupyter-slideshow-0.1.6
vscode-pylance	ms-python	2026.2.103	ms-python.vscode-pylance-2026.2.103
vscode-python-envs	ms-python	1.33.2026052801	ms-python.vscode-python-envs-1.33.2026052801-win32-x64
vscode-python-typehint	njqdev	1.5.1	njqdev.vscode-python-typehint-1.5.1

C# Settings

Setting	Value
preferCSharpExtension	false
compilerDiagnosticScope	openFiles
analyzerDiagnosticScope	openFiles
enableXamlTools	true
useServerGC	true

System Info

Item	Value
CPUs	12th Gen Intel(R) Core(TM) i5-12500H (16 x 3110)
GPU Status	2d_canvas: enabled GPU0: VENDOR= 0x8086, DEVICE=0x46a6 [Intel(R) Iris(R) Xe Graphics], DRIVER_VENDOR=Intel, DRIVER_VERSION=30.0.101.1660 ACTIVE GPU1: VENDOR= 0x8086, DEVICE=0x46a6 [Intel(R) Iris(R) Xe Graphics], DRIVER_VERSION=30.0.101.1660 GPU2: VENDOR= 0x8086, DEVICE=0x46a6 [Intel(R) Iris(R) Xe Graphics], DRIVER_VERSION=30.0.101.1660 GPU3: VENDOR= 0x1414, DEVICE=0x008c [Microsoft Basic Render Driver], DRIVER_VERSION=10.0.26100.8328 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 webgpu: enabled webnn: disabled_off
Load (avg)	undefined
Memory (System)	23.69GB (12.03GB free)
Process Argv	--crash-reporter-id 982e7db6-d247-44ff-a7bf-4067606b0c83
Screen Reader	no
VM	0%

A/B Experiments

vsliv368:30146709
pythonvspyt551cf:31249598
nativeloc1:31118317
dwcopilot:31158714
dwoutputs:31242946
copilot_t_ci:31333650
g012b348:31231168
pythonrdcb7:31268811
pythonpcpt1cf:31399617
6518g693:31302842
6abeh943:31336334
envsactivate1:31349248
editstats-enabled:31346256
cloudbuttont:31366566
3efgi100_wstrepl:31403338
839jf696:31457053
cp_cls_t_966_ss:31454198
inlinechat_v2_hd992725:31445440
4je02754:31455664
8hhj4413:31478653
38bie571_auto:31426784
cp_cls_t_1081:31454832
conptydll_true:31485575
ia-use-proxy-models-svc:31446143
e9c30283:31453065
test_treatment2:31471001
46204921:31447328
idci7584:31454084
nes_chat_context_enabled:31451401
e3e4d672:31454087
ei9d7968:31462942
de16b994:31458079
89g7j272:31506658
7e884298:31462391
7e187181:31482583
i2gc6536:31472020
52612955:31508042
h08i8180:31475367
23c7c724:31520045
ddid_t:31478204
hmra_i5g22:31518061
getcmakediagnosticsoff:31489825
f_rl1_7dj4g856:31519684
bjc72774_agent_sandbox:31505880
7df3h592:31491241
cp_cls_t_1082:31516087
logging_enabled_new:31490725
nes-extended-cfe-ctrl:31520692
jb_cp_cls_c_632:31517842
cg448276_tst_on:31503513
32d76977:31503652
ha629193:31508444
31fi7170_t:31517328
a1ije391_t:31520709
05755904:31517511
45j1j371_treat:31518485

[davidwengier]

@NEOSDEVNIC Thanks for reporting this. When formatting logs errors, its hard for us to track down what is going on without specific info about your files/project. To solve this we've added extra formatting specific logging to our formatting engine to help with this, but it has to be enabled explicitly. The instructions for turning on the extra logging are here: https://aka.ms/razor-formatting-issue

If you could enable this logging, re-open VS Code, and perform your formatting operation again, that will create a folder on disk with all of the info we need to solve this problem. If you can then zip up the folder and attach it to this issue, we'll be able to get this resolved.