Nuget Restore failure?

[JakeRadMSFT]

I'm getting nuget restore failures but not really sure how to fix?

2026-03-16 12:22:44.955 [error] /Users/jakerad/dev/tools/ref/dotnet-project-system/dotnet-project-system-vscode/src/Microsoft.ProjectSystem.Managed.VSCode.Services/Microsoft.ProjectSystem.Managed.VSCode.Services.csproj : error MSB4242: SDK Resolver Failure: "The NuGet-based SDK resolver failed to run because NuGet assemblies could not be located. Check your installation of MSBuild or set the environment variable "MSBUILD_NUGET_PATH" to the folder that contains the required NuGet assemblies. System.IO.FileLoadException: Could not load file or assembly 'NuGet.Packaging, Version=7.0.2.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'. Access is denied.
2026-03-16 12:23:02.191 [error] /Users/jakerad/dev/tools/ref/dotnet-project-system/dotnet-project-system-vscode/src/Microsoft.TemplateEngine.VSCode/Microsoft.TemplateEngine.VSCode.csproj : error MSB4014: The build stopped unexpectedly because of an internal failure.
2026-03-16 12:23:02.191 [error] /Users/jakerad/dev/tools/ref/dotnet-project-system/dotnet-project-system-vscode/src/Microsoft.TemplateEngine.VSCode/Microsoft.TemplateEngine.VSCode.csproj : error MSB4014: Microsoft.Build.BackEnd.SdkResolution.SdkResolverException: The NuGet-based SDK resolver failed to run because NuGet assemblies could not be located. Check your installation of MSBuild or set the environment variable "MSBUILD_NUGET_PATH" to the folder that contains the required NuGet assemblies. System.IO.FileLoadException: Could not load file or assembly 'N
2026-03-16 12:23:02.192 [info] uGet.Packaging, Version=7.0.2.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35'. Access is denied.

[claudiaregio]

@lifengl could you help with RCA here? Jake was opening the dotnet project system repo

[JakeRadMSFT]

We should log all msbuild_ env vars and path to msbuild that is loaded.

[lifengl]

not sure what exactly we can do here as those errors are coming from 'dotnet restore' command, and we don't really have insights for detailed errors like this. I think we logged the SDK resolved? It is an issue the SDK team should provide some help? (Maybe helping user with errors can be Copilot feature?)