MSBUILD : error MSB1003: Specify a project or solution file. The current working directory does not contain a project or solution file.

Describe the issue

1.Not a regression.
2.Medium priority.

MSBUILD : error MSB1003: Specify a project or solution file. The current working directory does not contain a project or solution file.

Collect logs

csdevkit-logs-2026-08-06T09-41-00.zip

Steps to reproduce

1.Create a Project1 such as C# Console App in Folder1 (No solution file exist).
2.In C# Project Details, right click the Folder1->Build/Rebuild.

Expected behavior

1.When there is no solution file in the workspace, the context menu for "C# Project Details" does not include the Build or Rebuild options; these options appear only when a solution file is present.
2.Or during the build process, activate the dropdown menu for creating a solution file.

3. I’m not quite sure what the best expectations would be, but in any case, it shouldn't have just flashed by like that.

Note that the build succeeds when a solution file is present.

Environment information

.NET Install Tool: Pre-release 3.1.0
C# Dev Kit Extension: Pre-release v3.29.195
C# Extension: Pre-release v2.148.23
.NET SDKs:  11.0.100-preview.6.26359.118
VSCode Stable: 1.132.0
Platform: Windows X64 

Start with the C# Project Details context menu and its Build/Rebuild actions, reproducing the failure with a C# project that has no solution file. Done means the workflow no longer briefly shows MSB1003: the actions should be unavailable without a solution, or the build flow should offer solution creation.