There was a communication/transmission error. Please restart. If the problem persists, contact customer support.

This error occurs when the Blizzard Update Agent is unable to connect with our server. Follow the steps below to resolve the issue.

  1. If you're using a wireless connection, optimize your internet connection.
  2. Proxy servers can cause connection issues and may be enabled by mistake or by a malicious program. Disable your proxy.
  3. Update Adobe Flash Player to resolve any issues an outdated plugin may cause.
  4. You may experience errors when Blizzard Update Agent files are missing or corrupt. Delete the Battle.net Tools folder to have the Update Agent automatically re-create necessary files.

Tried everything here?

If you've tried all of these steps and still need assistance, please visit our Technical Support Forum (World of Warcraft) (StarCraft II) (Diablo III) (Hearthstone) (Heroes of the Storm) (Overwatch) or contact us.