This works within the framework of the project, but not from the solution level. You can add folders at the solution level, but solution-level folders are not mapped to file system folders.
This will work if you have a project in the same folder. But you would include the โfolderโ in the project, not in the solution.
To add files from this folder, use Add> Existing Item. But the files you added this way will go to your Solution Items folder, which is probably not what you wanted to do. The Solution Items folder is simply mapped to the actual solution folder.
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