Quick fix: restart the Battle.net Agent

A bug report on the official forums describes the Forever beta failing to start because the Battle.net Agent keeps the shared game data locked.

  1. Quit Battle.net from the system tray or menu bar.
  2. Windows: open Task Manager and end Agent.exe and Battle.net.exe if they are still running. Mac: quit them in Activity Monitor.
  3. Open Battle.net again and press Play.

Expected: the game opens normally. If it does, the Agent lock was the cause.

If it still won’t start

  1. Scan and Repair. Click the gear next to Play and choose Scan and Repair. Expected: damaged files are downloaded again.
  2. Check the version. Make sure the Game Version menu shows World of Warcraft: Forever (or Forever Beta), not Classic or the modern game.
  3. Update graphics drivers. Blizzard recommends this before installing Forever.
  4. Run Battle.net as administrator (Windows) once, then try again.
  5. Disable overlays (Discord, Steam, recording tools) temporarily.

If the game starts but you cannot log in

That is a different problem — see BLZ51901016 for disconnects and beta access if the account has no entitlement.

Once the game runs, check addons for Forever-compatible versions — an outdated addon can also stop the interface from loading.