Account and login

Failed to Verify Authentication (AuthenticationUnavailableException)

What the log looks like

com\.mojang\.authlib\.exceptions\.authenticationunavailableexception: null
failed to verify authentication[\s\S]{0,120}yggdrasilsocialinteractionsservice\.checkprivileges

How to fix it

  1. If your game actually crashed or froze, scroll to the very bottom of latest.log or check the crash-reports folder for the real fatal error, because AuthenticationUnavailableException during startup does not close the game.
  2. If you are unable to join multiplayer servers, log out of your Microsoft account in your Minecraft launcher and sign back in to generate a fresh session token.
  3. Check your Windows hosts file (C:\Windows\System32\drivers\etc\hosts) and remove any lines referencing mojang.com or minecraftservices.com left behind by third-party account tools.
  4. Temporarily disable any VPN, proxy, or strict firewall rules that might block Java (javaw.exe) from reaching https://api.minecraftservices.com.
LoadersVanilla, Forge, Neoforge, Fabric, Quilt
SeverityWorth checking
CategoryAccount and login

Check your own log

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