Signing Into Xbox Live on Xbox 360 Today: Impossible—Servers Shut Down 2020

You cannot sign into the modern Xbox network on an Xbox 360.

Why

• Separate services: Xbox 360 used "Xbox Live for Xbox 360." Modern consoles use "Xbox Network" (renamed 2021). They are incompatible.
• Server shutdown: Microsoft ended Xbox 360 Live support July 13, 2020. Matchmaking, marketplace, cloud saves, parties — all offline.

What Still Works on 360 (Offline/Local)

• Single-player campaigns.
• Local split-screen / System Link (LAN) multiplayer.
• Installed digital games (if licenses valid).
• Media apps (Netflix, YouTube) — some still function if app servers remain.
• DVD/Blu-ray playback.

What's Gone

• Online multiplayer, matchmaking, leaderboards.
• Marketplace purchases / redownloads.
• Cloud saves.
• Messages, friends list, parties.

Workaround for Online

• Insignia — fan-run replacement for original Xbox Live (not 360).
• XLink Kai — enables System Link over internet (tunnel LAN) for 360.

The 360's online era is over. Offline/local/System Link + XLink Kai are the only multiplayer paths left.