This error is generally presented when trying to log in on a console device while the servers are down.

Troubleshooting Error #0 in World of Warcraft

How to resolve the error "There was a problem restoring your deleted character. Please try again later." 

What to do if you are receiving an error when playing Duels

What to do if the Battle.net desktop app is stuck in a Scan & Repair loop

Troubleshooting for game crashes with error "The application encountered an unexpected error"

Troubleshooting for error 1016 in Diablo III

What to do if you get the error HF-1 in Overwatch

Information about the error "There was a problem retrieving items from the store. (Code 396009)."

Troubleshooting steps for the Overwatch error HF - 503