This error message appears while logging in to the game with the message that the player was disconnected from the server.
Troubleshooting steps for payment error: Oops! This needs your attention.
Troubleshooting steps for payment error: Unexpected error code from complete:0.
What to do if you receive a generic error when sending a gift to a friend.
What to do if you receive this error in the Battle.net Shop.
Troubleshooting for game crashes with error "The application encountered an unexpected error"
Information about this error when adding a phone number or an Authenticator to a Battle.net account
How to obtain error logs for Blizzard games
Information about password restrictions and requirements for Battle.net accounts
Information regarding steps you can take if your email address is already in use on an account.