this week when I went on and the update appeared for the Duracell car park, it started downloading and is now stuck at ‘ready to start 100%’. once this appeared I started the game and went through the sync which worked fine. after pressing A at the start menu, the installing…please wait section appears on the game. this has been stuck at 75% for a day. also all car packs/expansion and VIP pass uninstalled? Anyone know whats up here and a cure for the problems?
Despite the interface telling you “Ready to start” when an update is being installed, you should always wait until the update is completely finished and removed from your queue. For whatever reason, it seems that Forza titles have a real hard time operating properly when updates and downloadable content are not entirely installed. Even when shown at 100%, the update is not fully installed until it disappears from the queue on your Xbox One Games & Apps menu screen.
I would recommend you perform a complete power cycle of your Xbox One (do not just turn off/on) and return to the Games & Apps menu to see if there are still items in the queue. If not, go to the “Manage Game” screen for Forza Horizon 2 and see if all add-on content shows as being installed. Upon verifying, launch Forza Horizon 2 to see if it loads correctly.