Achievements unlock locally but fail to sync to Xbox Live. Common causes & fixes:
Quick Fixes (Try First)
Sign Out / Sign In: Guide → Profile → Sign Out. Wait 10s. Sign In. Forces fresh token.
Hard Reset Console: Hold power button 10s → Full shutdown. Unplug 30s. Reboot.
Check Xbox Live Status:Xbox Live Status → "Xbox 360: Purchase & Content Usage", "Social & Gaming" must be Green.
Network Test: Settings → System → Network Settings → Test Xbox Live Connection. Fix any "MTU", "UPnP", "NAT" warnings.
Deeper Fixes
Clear System Cache (3x): Settings → System → Storage → Highlight HDD → Y → Clear System Cache. Do 3 times. Clears corrupt local achievement cache.
Delete Corrupt Profile Cache: Settings → System → Storage → Hard Drive → Gamer Profiles → Your Profile → Delete **Profile Only** (keeps saves). Re-download profile on sign-in.
Check Date/Time: Settings → System → Console Settings → Clock. Must be correct (auto from Live). Wrong time = SSL cert failure = no sync.
Offline Unlock Glitch: Earned achievements offline? They sync on next sign-in. If not, re-earn trigger (impossible for story) or use Xbox 360 Achievement Unlocker (Horizon) — ban risk, offline only.
Known Problematic Games
Fallout 3 / NV (huge save = sync timeout), GTA IV (GFWL conflict), Red Dead Redemption, Call of Duty: MW2/BO (demonware sync).
Fix: Earn 1 simple achievement in another game (e.g., Hexic HD free) → forces full sync sweep.
If Nothing Works
Contact Xbox Support → Chat/Callback. Provide: Console ID (Settings → System → Console Settings → System Info), Gamertag, Game Title, Achievement Name, Date/Time earned.
They can force server-side sync or identify account suspension.
Sync usually resolves within 24h after fix. Check account.xbox.com/achievements (web) — updates faster than console.
