Unable to start a debug session in visual studio 2026

ClaudiaPautz

Hi,

I am using visual studio community 2026 vs 18.0.2, and PHP Tools for Visual Studio Version: 1.88.18138.2026 Release Date: november 25 of 2025.

The Error shown is:

Unable to Start Debugging on the Web Server. Unable to start debugging. Legacy script debugging (Internet Explorer, cscript, etc.) is no longer supported in this version of Visual Studio. The PHP Tools for Visual Studio failed to attach to the Web Server. Please contact vendor for assistance.

JakubMisek

ClaudiaPautz, thank you for reporting that.

For now, as a workaround, try disabling "Script Debugging" in the Debug Run toolbar.

ClaudiaPautz

I forgot to say that the same project configuration works flawless in visual studio community 2022.
Thanks in advance for any suggestions.

ClaudiaPautz

Thanks for the suggestion, but the script debugging option is already disabled.

MiloslavBeno

May I ask what browser is selected in the Debug Run toolbar?

So far, we haven't been able to reproduce this on VS 2026 Insiders edition. We will try on general release and get back to you.

ClaudiaPautz

I apologize for the delay.
The browser is Google Chrome.

MiloslavBeno

Hi,

Thank you. May I also ask to check what project type is ds2018? We do not currently support Dev Tunnels on PHP Web Projects, so they shouldn't be visible in the Debug Run Panel :-/

ClaudiaPautz

ds2018 is a php 8.1 project, no tunnels...as I told, this exact project works flawless in visual studio community 2022. The debug in vs 2022 works just fine.
below is a screen shot of the project properties:

ClaudiaPautz

Hi!

I just installed the last version(1.88.18183.2026 released at december 5), and the error still remains.

Any progress?

Thanks.

MiloslavBeno

Hi,

we are still unable to replicate. Maybe it's some other settings we are missing - because when script debugging is disabled VS shouldn't try to initiate script debugger, which is what it fails according to the message. I will write here as soon as we know more.

Thank you for your patience

CharleneGray

I am having the exact same issue.

JakubMisek

May I ask what Visual Studio components you have installed? You can check it in
Visual Studio - Help - About Microsoft Visual Studio -> Copy Info

Our (working) installation has the following:

info.txt

1kB

And what workloads are installed in "Visual Studio Installer" program - More - Export Configuration -> Review Details -> Export

.vsconfig file:

{
  "version": "1.0",
  "components": [
    "Microsoft.VisualStudio.Component.CoreEditor",
    "Microsoft.VisualStudio.Workload.CoreEditor",
    "Microsoft.Net.Component.4.8.SDK",
    "Microsoft.Net.Component.4.7.2.TargetingPack",
    "Microsoft.Net.ComponentGroup.DevelopmentPrerequisites",
    "Microsoft.VisualStudio.Component.TypeScript.TSServer",
    "Microsoft.VisualStudio.ComponentGroup.WebToolsExtensions",
    "Microsoft.VisualStudio.Component.JavaScript.TypeScript",
    "Microsoft.VisualStudio.Component.JavaScript.Diagnostics",
    "Microsoft.VisualStudio.Component.Roslyn.Compiler",
    "Microsoft.Component.MSBuild",
    "Microsoft.VisualStudio.Component.Roslyn.LanguageServices",
    "Microsoft.VisualStudio.Component.TextTemplating",
    "Component.Microsoft.VisualStudio.RazorExtension",
    "Microsoft.VisualStudio.Component.IISExpress",
    "Microsoft.VisualStudio.Component.NuGet",
    "Microsoft.VisualStudio.Component.MSODBC.SQL",
    "Microsoft.VisualStudio.Component.SQL.LocalDB.Runtime",
    "Microsoft.VisualStudio.Component.SQL.CLR",
    "Microsoft.VisualStudio.Component.MSSQL.CMDLnUtils",
    "Microsoft.Component.ClickOnce",
    "Microsoft.VisualStudio.Component.DiagnosticTools",
    "Microsoft.VisualStudio.Component.ManagedDesktop.Core",
    "Microsoft.VisualStudio.Component.SQL.SSDT",
    "Microsoft.VisualStudio.Component.SQL.DataSources",
    "Component.Microsoft.Web.LibraryManager",
    "Microsoft.VisualStudio.ComponentGroup.Web",
    "Microsoft.NetCore.Component.Runtime.10.0",
    "Microsoft.NetCore.Component.SDK",
    "Microsoft.VisualStudio.Component.FSharp",
    "Microsoft.ComponentGroup.ClickOnce.Publish",
    "Microsoft.NetCore.Component.DevelopmentTools",
    "Microsoft.VisualStudio.Component.FSharp.WebTemplates",
    "Microsoft.VisualStudio.Component.DockerTools",
    "Microsoft.NetCore.Component.Web",
    "Microsoft.VisualStudio.Component.WebDeploy",
    "Microsoft.VisualStudio.Component.AppInsights.Tools",
    "Microsoft.VisualStudio.Component.Web",
    "Microsoft.Net.Component.4.8.TargetingPack",
    "Microsoft.Net.ComponentGroup.4.8.DeveloperTools",
    "Microsoft.VisualStudio.Component.AspNet",
    "Component.Microsoft.VisualStudio.Web.AzureFunctions",
    "Microsoft.VisualStudio.ComponentGroup.AzureFunctions",
    "Microsoft.VisualStudio.ComponentGroup.Web.CloudTools",
    "Microsoft.VisualStudio.Component.EntityFramework",
    "Microsoft.VisualStudio.Component.IntelliCode",
    "Microsoft.NetCore.Component.Runtime.8.0",
    "Microsoft.VisualStudio.Workload.NetWeb",
    "Microsoft.VisualStudio.Component.ManagedDesktop.Prerequisites",
    "Microsoft.VisualStudio.Workload.ManagedDesktop",
    "Microsoft.Net.Component.4.6.TargetingPack",
    "Microsoft.VisualStudio.Component.VSSDK",
    "Microsoft.VisualStudio.ComponentGroup.VisualStudioExtension.Prerequisites",
    "Microsoft.Component.CodeAnalysis.SDK",
    "Microsoft.VisualStudio.Workload.VisualStudioExtension"
  ],
  "extensions": [
    "https://marketplace.visualstudio.com/items?itemName=MLNET.ModelBuilder2022",
    "https://marketplace.visualstudio.com/items?itemName=DEVSENSE.PHPToolsforVisualStudio2022"
  ]
}

ClaudiaPautz

Hey, JakubMisek !

Answering your questions:

Components Installed, grabbed from Visual Studio - Help - About Microsoft Visual Studio -> Copy Info

Visual C++ 2026   00529-30000-00000-AA837
Microsoft Visual C++ 2026

.NET MAUI Tools   18.0.345 (fbde6c01f0)
Visual Studio extension to enable .NET MAUI development.

.NET MAUI UI Tools   18.0.1.33 (remotes/origin/HEAD@44462085bc)
Visual Studio extension to enable .NET MAUI UI tools.

ADL Tools Service Provider   1.0
This package contains services used by Data Lake tools

ASA Service Provider   1.0

ASP.NET and Web Tools   18.0.338.63737
ASP.NET and Web Tools

Azure App Service Tools v3.0.0   18.0.338.63737
Azure App Service Tools v3.0.0

Azure Data Lake Tools for Visual Studio   2.6.5000.0
Microsoft Azure Data Lake Tools for Visual Studio

Azure Functions and Web Jobs Tools   18.0.338.63737
Azure Functions and Web Jobs Tools

Azure Stream Analytics Tools for Visual Studio   2.6.5000.0
Microsoft Azure Stream Analytics Tools for Visual Studio

C# Tools   5.0.0-2.25574.6+7f327e02b43a2486faa9cfdf0a1eae34c06e2d1a
C# components used in the IDE. Depending on your project type and settings, a different version of the compiler may be used.

Cookiecutter   17.0.25266.3
Provides tools for finding, instantiating and customizing templates in cookiecutter format.

GitHub Copilot   18.0.981.45449
GitHub Copilot is an AI pair programmer that helps you write code faster and with less work.

Microsoft Azure Hive Query Language Service   2.6.5000.0
Language service for Hive query

Microsoft Azure Stream Analytics Language Service   2.6.5000.0
Language service for Azure Stream Analytics

Mono Debugging for Visual Studio   18.0.15 (76f6142551)
Support for debugging Mono processes with Visual Studio

Node.js Tools   1.5.70729.1 Commit Hash:7e362c1cf2c48c547a94b4eee7f276acca547563
Adds support for developing and debugging Node.js apps in Visual Studio

NuGet Package Manager   7.0.2
NuGet Package Manager in Visual Studio. For more information about NuGet, visit https://docs.nuget.org/

Office Developer Tools for Visual Studio   18.0.36609.00
Microsoft Office Developer Tools for Visual Studio

PHP Tools for Visual Studio   1.88.18183.2026
PHP Tools extend Visual Studio with a set of features to build PHP applications more efficiently. It makes code more readable, easier to navigate, and clean.

Python - Django support   17.0.25266.3
Provides templates and integration for the Django web framework.

Python - Profiling support   17.0.25266.3
Profiling support for Python projects.

Python with Pylance   17.0.25266.3
Provides IntelliSense, projects, templates, debugging, interactive windows, and other support for Python developers.

Razor (ASP.NET Core)   18.0.2.2551302+48a2659b91e7032c97ea024751a6ea9469a94d7f
Provides languages services for ASP.NET Core Razor.

SQL Server Data Tools   18.0.172.3
Microsoft SQL Server Data Tools

Test Adapter for Boost.Test   1.0
Enables Visual Studio's testing tools with unit tests written for Boost.Test.  The use terms and Third Party Notices are available in the extension installation directory.

Test Adapter for Google Test   1.0
Enables Visual Studio's testing tools with unit tests written for Google Test.  The use terms and Third Party Notices are available in the extension installation directory.

ToolWindowHostedEditor   1.0
Hosting json editor into a tool window

TypeScript Tools   18.0.1114.2009
TypeScript Tools for Microsoft Visual Studio

Visual Basic Tools   5.0.0-2.25574.6+7f327e02b43a2486faa9cfdf0a1eae34c06e2d1a
Visual Basic components used in the IDE. Depending on your project type and settings, a different version of the compiler may be used.

Visual C++ for Cross Platform Mobile Development (Android)   15.0.11104.47
Visual C++ for Cross Platform Mobile Development (Android)

Visual F# Tools   18.0.0-rc2.25522.6+db81a081913bbaa32e528305723c07d98fd598b8
Microsoft Visual F# Tools

Visual Studio IntelliCode   2.2.3152.23957
AI-assisted development for Visual Studio.

VSPackage Extension   1.0
VSPackage Visual Studio Extension Detailed Info

Workflow Manager Tools 1.0   1.0
This package contains the necessary Visual Studio integration components for Workflow Manager.

---------------------------------------------------------------------------------------------------------------------------------------------------------------------

Workloads, grabbed from "Visual Studio Installer" program - More - Export Configuration -> Review Details -> Export

{
  "version": "1.0",
  "components": [
    "Microsoft.VisualStudio.Component.CoreEditor",
    "Microsoft.VisualStudio.Workload.CoreEditor",
    "Microsoft.Net.Component.4.8.SDK",
    "Microsoft.Net.Component.4.7.2.TargetingPack",
    "Microsoft.Net.ComponentGroup.DevelopmentPrerequisites",
    "Microsoft.VisualStudio.Component.TypeScript.TSServer",
    "Microsoft.VisualStudio.ComponentGroup.WebToolsExtensions",
    "Microsoft.VisualStudio.Component.JavaScript.TypeScript",
    "Microsoft.VisualStudio.Component.JavaScript.Diagnostics",
    "Microsoft.VisualStudio.Component.Roslyn.Compiler",
    "Microsoft.Component.MSBuild",
    "Microsoft.VisualStudio.Component.Roslyn.LanguageServices",
    "Microsoft.VisualStudio.Component.TextTemplating",
    "Component.Microsoft.VisualStudio.RazorExtension",
    "Microsoft.VisualStudio.Component.IISExpress",
    "Microsoft.VisualStudio.Component.NuGet",
    "Microsoft.VisualStudio.Component.MSODBC.SQL",
    "Microsoft.VisualStudio.Component.SQL.LocalDB.Runtime",
    "Microsoft.VisualStudio.Component.SQL.CLR",
    "Microsoft.VisualStudio.Component.MSSQL.CMDLnUtils",
    "Microsoft.Component.ClickOnce",
    "Microsoft.VisualStudio.Component.DiagnosticTools",
    "Microsoft.VisualStudio.Component.ManagedDesktop.Core",
    "Microsoft.VisualStudio.Component.SQL.SSDT",
    "Microsoft.VisualStudio.Component.SQL.DataSources",
    "Component.Microsoft.Web.LibraryManager",
    "Microsoft.VisualStudio.ComponentGroup.Web",
    "Microsoft.NetCore.Component.Runtime.10.0",
    "Microsoft.NetCore.Component.SDK",
    "Microsoft.VisualStudio.Component.FSharp",
    "Microsoft.ComponentGroup.ClickOnce.Publish",
    "Microsoft.NetCore.Component.DevelopmentTools",
    "Microsoft.VisualStudio.Component.FSharp.WebTemplates",
    "Microsoft.VisualStudio.Component.DockerTools",
    "Microsoft.NetCore.Component.Web",
    "Microsoft.VisualStudio.Component.WebDeploy",
    "Microsoft.VisualStudio.Component.AppInsights.Tools",
    "Microsoft.VisualStudio.Component.Web",
    "Microsoft.Net.Component.4.8.TargetingPack",
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    "Component.Microsoft.VisualStudio.Web.AzureFunctions",
    "Microsoft.VisualStudio.ComponentGroup.AzureFunctions",
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    "Microsoft.VisualStudio.Component.WslDebugging",
    "Microsoft.VisualStudio.Component.IntelliCode",
    "Component.VisualStudio.GitHub.Copilot",
    "ComponentGroup.Microsoft.NET.AppModernization",
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    "maui.windows",
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    "Microsoft.VisualStudio.ComponentGroup.Maui.Blazor",
    "Microsoft.VisualStudio.ComponentGroup.WebToolsExtensions.TemplateEngine",
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    "Microsoft.VisualStudio.Workload.NetCrossPlat",
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    "Microsoft.VisualStudio.Component.DotNetModelBuilder",
    "Microsoft.ComponentGroup.Blend",
    "Microsoft.VisualStudio.Workload.ManagedDesktop",
    "Microsoft.VisualStudio.Component.VC.ATL",
    "Microsoft.VisualStudio.Component.VC.Redist.14.Latest",
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    "Microsoft.VisualStudio.Component.Windows11Sdk.WindowsPerformanceToolkit",
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    "Microsoft.VisualStudio.ComponentGroup.WebToolsExtensions.CMake",
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    "Microsoft.VisualStudio.Component.VC.TestAdapterForBoostTest",
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MiloslavBeno

Hi!

Finally, we’ve been able to replicate the issue. It is caused by the legacy PHP project system in Visual Studio 2026.

For now, the easiest workaround is to use File → Project From Existing Code, choose PHP, select the project folder, and click Next. This will create a new project file using the new project system, which will immediately resolve the issue.

We will also look into what can be done to patch the legacy project system; however, we strongly recommend migrating to the new project system, as it is more robust and actively maintained.

Please let us know if you need any assistance with the migration.

Best regards!

ClaudiaPautz

Hi!

Just to thank you, because I've recreated the project and everything worked fine!

Best Regards!

MiloslavBeno

Fixed in the upcoming update.

Thank you!