BLZBNTBNA00000640

Updated: 3 years ago
Article ID: 23636

Common Problems

Something went wrong with a security certificate.
Error Code: BLZBNTBNA00000640

The Battle.net desktop app can't confirm that it has a secure connection to the Battle.net servers.

  1. Press reload to refresh the page. If the issue persists, restart the client to clear up any temporary issues.
  2. If you're using a wireless connection, optimize your internet connection to rule out a connection issue.
  3. Run a security scan to remove any viruses or malware infections.
  4. Run Software Update to check for pending updates to software, drivers, and firmware.
  5. Uninstalling and reinstalling the Battle.net App may resolve rare launcher issues.

Tried everything here?

If you have tried these steps and still require assistance, visit our Technical Support Forums (World of Warcraft) (StarCraft II) (Diablo III) (Hearthstone) (Heroes of the Storm) (Overwatch) or contact us.