Jonathan, I just had the same issue and figured it out. Super easy! i went to Local Disk (C:)> Users>Your computer name>AppData>Roaming>Lockheed Martin>Prepar3D v4. In there you will find "add-ons" file. youll see something like [Package.0] PATH=C:\Users\Blake Roark Game\Documents\Prepar3D v4 Add-ons\Flightbeam - KDEN ACTIVE=false REQUIRED=false Which are the add-ons that are installed but not enabled. I deleted all the info, saved the file, and started P3d v4 and i was then prompted to enable. Now ALL of my add-ons work.