The "Preparing game data" screen is rarely a true error. It becomes a problem only when:
In those cases, uninstall the game, delete the Blizzard Entertainment folders from both ProgramData and your Documents folder, and perform a clean reinstall. starcraft ii preparing game data
There are several reasons why "Starcraft II preparing game data" can seem to drag on indefinitely: The "Preparing game data" screen is rarely a true error
If you only experience "Preparing game data" in Co-op or Arcade games (like Direct Strike or Squadron TD), the issue is different. In these modes, the host player (usually the first person in the lobby) has a slow computer. In those cases, uninstall the game, delete the
The Fix: When you host a lobby, the game compiles data for every custom asset on your machine. If you host, you suffer. If you join, you don't.
Do not use the "Scan and Repair" tool in Battle.net. It rarely fixes shader issues. Do this manually.