MSB4216 when trying new RC 2 .NET MSBuild Tasks with .NET Framework MSBuild feature

[bording]

I'm trying out the new feature to use .NET MSBuild Tasks with .NET Framework MSBuild that shipped in RC 2, but when trying to have Visual Studio 2026 use the task, it's not working.

The build starts, and at first it looks like it's hanging, but eventually it times out and I get the following error:

error MSB4216: Could not run the "SqlPersistenceScriptBuilderTask" task because MSBuild could not create or connect to a task host with runtime "NET" and architecture "x64".  Please ensure that (1) the requested runtime and/or architecture are available on the machine, and (2) that the required executable "C:\Program Files\dotnet\sdk\10.0.100-rc.2.25502.107" exists and can be run

I have a draft PR for the changes I've made to our MSBuild task here, but I'm fairly sure I've made the changes as described in the RC 2 release notes correctly.

I've also included the binlogs and CommTrace files from VS for the failed build. Looking through it, I'm not really seeing anything that stands out, though this does seem a bit odd:

Could not run the "SqlPersistenceScriptBuilderTask" task because MSBuild could not create or connect to a task host with runtime "NET" and architecture "x64".  Please ensure that (1) the requested runtime and/or architecture are available on the machine, and (2) that the required executable "C:\Program Files\dotnet\sdk\10.0.100-rc.2.25502.107" exists and can be run.

MSBuildLogs.zip

Building the project from the command line works fine, though it's not trying to use the task host from that build.

[baronfel]

First off, thanks for trying out the feature! We have been dogfooding internally as well and have found a bug that's a blocker for the publicly-released VS version of MSBuild - our feature doesn't handle paths to dotnet with spaces in them.

This should be resolved in #12644, which has been approved. We don't expect to be able to get this into the next preview of dev18, but I believe we're aiming for the one after that due to the schedules involved. This won't require an update to the .NET SDK at all, only Visual Studio/.NET Framework MSBuild.

As a condolence we're also getting in #12642, which means you'll only have to set Runtime="NET", none of the TaskFactory or Condition changes will be required.

Finally, I did take a look at your draft PR and it looks correct to me.

[bording]

First off, thanks for trying out the feature!

I have been wanting a feature like this for so long, I had to try it out immediately!

We have been dogfooding internally as well and have found a bug that's a blocker for the publicly-released VS version of MSBuild - our feature doesn't handle paths to dotnet with spaces in them.

That's definitely a bit unfortunate since, you know, Program Files!

Not needing to duplicate the UsingTask definitions to add the TaskFactory setting will be nice, so I'll keep an eye out for when the fix ships and give it another try.