This error occurs when your connection to our servers is blocked. This may be caused by a third-party program.
You have attempted to connect to an invalid server. If this problem persists, please contact Customer Support.
How to swap email addresses between two accounts
Standalone patches are downloaded outside of the game launcher or the Desktop app.
Blizzard servers could not be reached or may be offline.
Your chipset driver is older than is recommended.
The Battle.net Update Agent detected that one or more system components do not meet system requirements.
Troubleshooting steps for Error BLZBNTBNA0000138F.