The folder location for .addin files for all users.
Namespace: Autodesk.Revit.ApplicationServices
Assembly: RevitAPI (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0)
Since: 2014
Namespace: Autodesk.Revit.ApplicationServices
Assembly: RevitAPI (in RevitAPI.dll) Version: 2015.0.0.0 (2015.0.0.0)
Since: 2014