To add an existing folder to a project
1. In the Project Explorer, select the project or a project folder.
2. Right-click in the Project Explorer and select Add Folder...
3. Click the drop-down list in the name field showing the available folders.
4. Select the folder name
5. Enter notes (optional).
6. Press ‘OK’ to accept input.
This will include the existing folder in the project. Note, that the files within the folder is not included in the project at the same time.