You copied Stardew Valley from a friend's USB drive to D:\Games\Stardew . Simsync tries to find the game via the Windows Registry (e.g., HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall ). It fails, so it throws the "unable to find all paths" error.
Create a Simsync profile that includes both paths: the vanilla game folder AND the MO2 mod staging folder. The error disappears when both are validated. simsync unable to find all game paths
It never lies. Once you see the exact missing path, you are 90% of the way to a fix. Edit your profile, correct the path, or remove the offending line, and your syncs will run smoothly again. You copied Stardew Valley from a friend's USB
INFO: Scanning drive C:\ INFO: Scanning well-known folder: Documents WARN: Access denied: C:\Program Files\HiddenGame correct the path
# Linux/macOS ./simsync --verbose --log-file simsync_debug.log