A small number of users who:

Paste the modified save file and to match your original file’s name (the long string of characters).

For 99% of players, the best approach is to use a save editor on a to experience the cars in solo mode. If you want to race online with the full 100% garage without fear, you will have to earn it the old-fashioned way—or switch to the Steam version, which has no save protection.

Unlike the Steam version, which stores saves in standard user folders, the Microsoft Store utilizes encrypted, deeply nested AppData folders.

Forza Horizon 5 100% Save Game Microsoft Store (2021/2026 Edition)

Here are the primary methods and tools used by the modding community to circumvent these protections:

Pro: You keep your XUID. Con: Still a ban risk.