Merge pull request #12921 from MicrosoftDocs/ghogen-patch-67

Add explanatory note about folder structure

Author: prmerger-automator[bot]

docs/msbuild/how-to-build-specific-targets-in-solutions-by-using-msbuild-exe.md

@@ -34,6 +34,9 @@ msbuild SlnFolders.sln -target:NotInSlnfolder:Rebuild;NewFolder\InSolutionFolder
 
 Building a specific target also triggers other dependent targets to build.
 
+> [!NOTE]
+> The path used in the `targets` switch is not a filesystem path. It is a path in the solution's internal representation, and visible in **Solution Explorer**. For example, you can't use filesystem path syntax such as `.` or `..` in the `targets` switch. That is why a project referenced in another filesystem location like `NotInSlnFolder` doesn't require an explicit path, but a project within a solution folder `InSolutionFolder` does. Solutions can also have folders, created by **Add** > **Solution folder** in Visual Studio. Those folders are used to organize projects within the solution when viewed in **Solution Explorer** in Visual Studio. The layout in the filesystem can be different from the solution folder structure. See [Solution folders](../ide/solutions-and-projects-in-visual-studio.md#solution-folder).
+
 ## Troubleshooting
 
 If you would like to examine the solution project, you can use a debugging option provided by MSBuild to do so. Set the environment variable `MSBUILDEMITSOLUTION=1` and build your solution. This will produce an MSBuild file named *\<SolutionName>.sln.metaproj* that shows MSBuild's internal view of the solution at build time. You can inspect this view to determine what targets are available to build, and other configuration details.