dotnet publish errors with MSB4186 sdk 10.0.200

[ToSec-faha]

Describe the bug

Running dotnet publish with sdk version 10.0.200 errors with: MSB4186: Invalid static method invocation syntax.

I do not think we have any custom tasks that causes this.

I assume this is because a file contains ',' in its filename.

The publish still works if done through VS Studio 2026 - 18.4.0

I found similar issue:

• error MSB4186: Invalid static method invocation syntax: aspnetcore#31770

Exceptions (if any)

C:\Program Files\dotnet\sdk\10.0.200\Sdks\Microsoft.NET.Sdk\targets\Microsoft.NET.Publish.targets(851,9): error MSB4186: Invalid static method invocation syntax: "[MSBuild]::MakeRelative($(MSBuildProjectDirectory), C:\ProjectPath\wwwroot\css\Open_Sans_300,400,600,700.css)". Method '[MSBuild]::MakeRelative' not found. Static method invocation should be of the form: $([FullTypeName]::Method()), e.g. $([System.IO.Path]::Combine(`a`, `b`)). Check that all parameters are defined, are of the correct type, and are specified in the right order.

Further technical details

details of dotnet --info

.NET SDK: Version: 10.0.200 Commit: 40cd698e5c Workload version: 10.0.200-manifests.b7278506 MSBuild version: 18.3.0-release-26119-122+40cd698e5

Runtime Environment:
OS Name: Windows
OS Version: 10.0.26200
OS Platform: Windows
RID: win-x64
Base Path: C:\Program Files\dotnet\sdk\10.0.200\

- VS Studio 2026 - 18.4.0

[meum]

i ran into the same thing, with a file with comma in the filename inside the wwwroot folder. it works with 10.0.104 but fails with 10.0.200.

dotnet new web
mkdir wwwroot
touch wwwroot/my,file.txt
dotnet build

[tlaxanatos]

Also experiencing this issue with my build pipelines on 10.0.200.

[marcpopMSFT]

@JanKrivanek The error is coming from the code you added for IfDifferent. Does there need to be a fix on the SDK side or MSBuild side? #52275

We should fix this in servicing.

CC @baronfel @rainersigwald

[rainersigwald]

Workaround

For any affected file, add TargetPath metadata in the project.

For instance, with @meum's (excellent!) repro, adding

  <ItemGroup>
    <Content Update="wwwroot\my,file.txt" TargetPath="wwwroot\my,file.txt" />
  </ItemGroup>

to the project seems to work around the issue.

For a permanent fix, it looks like we can quote the paths, PR shortly.