Re: PBXConnection.CreateAdminAppObject() failed: Duplicate Name
Even if you don't have that connection inside of the Visual Studio connection manager, an App-Object with the same name may already exist. In that case it maybe the App Object called VSHelper.
Maybe you can go to the PBX interface (e. g. by directly accessing the PBX web interface or using the devices app), got to "PBX" and then "Objects". Search for the VSHelper object, delete it and try again.