The login servers received invalid information

What to do when a physical authenticator gets out of sync

What to do if you receive "Invalid Serial Number"

What to do if the serial number at the back of the physical authenticator is scratched off

what to do if player is unable to verify their account with the verification code

Error emerges when trying to restore the previous authenticator on a new device

Reasons your authentication may show an incorrect Geo-location when requesting approvals

Can't log into Battle.net website or get online when logging with the Battle.net desktop app.

More information about authenticator security codes

This is how to check if there is an error that the password is not correct