Information on troubleshooting connection and installation issues using another network.
Information about this error
Troubleshooting claiming a Call of Duty: Vanguard key
An authenticator is on the Battle.net account that you did not add.
Recovering a Battle.net Account when the email address has been forgotten
What to do if you can't claim your Call of Duty: Black Ops 4 key
What to do if you think another person or group of people has targeted a DDoS attack on you