That is odd. Any chance that the APJ file for the Sample Project 2016 is somehow damaged, and not being seen as a valid APJ file by AutoCAD Architecture? I have a similar view to yours in Windows 10 File Explorer, but in the Project Browser, I do not have a folder icon for Sample Project 2016 in the My Projects folder which I can open/go into in the Project Browser. Instead, with the My Projects folder current, I have a Sample Project 2016 APJ file which I can select, to set current.
The only Sample Project folders that do show in the Project Browser as folder icons are for versions I no longer have installed, and are likely leftovers from a beta install that were never fully cleaned up. Those folder do not have the full complement of project files and subfolders in them, just a single RPQ file, which only shows in File Explorer, not Project Browser.
Note: The reason there are two "Sample Project 2017" files, one an APJ and one a folder, is that the folder is a remnant from the 2017 beta, and the APJ is in a Windows folder called Sample Project 2018. I have not yet uninstalled the 2018 Beta, and they must not have bothered to update the sample project name for 2018 beta files.
David Koch
AutoCAD Architecture and Revit User
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