Outdated, corrupted, or missing folders or files can cause issues with the Blizzard Battle.net desktop app and game clients. In order to resolve these issues use the following steps:

Windows

  1. Close Blizzard processes.
    1. Press Ctrl + Shift + Esc to bring up the Task Manager.
    2. Click the Processes tab.
    3. Select all Agent, Blizzard, and game processes, and click End Process.
  2. Navigate to the folder containing the Battle.net directory:
    1. Press Windows key + R to open the Run dialogue.
    2. Type C:\ProgramData\ into the Open field and press Enter:
  3. Delete the Battle.net folder.
  4. Run the Blizzard Battle.net desktop app and update the game to see if the issue persists.

If the error persists after you try these steps, another program may be causing the problem. Restart your computer and delete the Battle.net folder one more time.

Mac

  1. Use Activity Monitor to quit all Agent, Blizzard, and game processes.
  2. Using Finder, click the Go menu and select Computer.
  3. Navigate to the /Users/Shared/Battle.net/Agent directory.
  4. Delete agent.db and relaunch the Battle.net.
  5. If the issue persists, delete the Agent folder inside the Battle.net directory and relaunch Battle.net.
  6. If the issue persists, go back to the /Users/Shared directory and delete the Battle.net folder.
  7. Launch the game using the Blizzard Battle.net desktop app.

If the error persists after you try these steps, another program may be causing the problem. Restart your computer and delete the Battle.net folder one more time.

Note: The above steps may cause the application to forget game install locations. If your games can’t be found, you will see Install on the game tab instead of Play. To find your installation, click Locate this game or run the game launcher.