This error occurs when game data needs to be compressed or when background downloaded patch data needs to be installed.
If you experience issues with the patch optimization process, such as the progress bar moving slowly or being stuck at 0%, it may be a display issue. Allow at least one hour for the optimization to finish.
- Make sure you run the launcher as an administrator so it has the permissions needed to update the game.
- You may experience issues when Blizzard Update Agent files are missing or corrupt. Delete the Battle.net Tools folder to have the Update Agent automatically re-create the necessary files.
- The way the Blizzard Update Agent installs and updates our games may cause security software to incorrectly profile the game launcher. Try disabling or temporarily uninstalling your security software.
- Be sure to disable read-only settings on any game and launcher executable files (files that end in .exe) in your game folder.
- If you are using a public network (like a university or hotel) and you continue to experience issues, contact the system administrator.
- If you still have issues during optimization, uninstall the game and then reinstall the game client.
Tried everything here?
Article ID: 6426