The "Preparing game data" phase requires free space to decompress temporary swap files. If your system drive (C:) has less than 10 GB free, or your game drive has less than 5 GB free, the process will stall. Many players mistakenly think the game just needs space for an update—but the preparing phase itself needs scratch space.
All of this lives in ( .SC2Data ), which are MPQ-like archives (similar to Blizzard’s older formats but evolved). Preparing game data means: starcraft 2 preparing game data
Blizzard has optimized this process over the last decade, but it remains inconsistent. The "Preparing game data" phase requires free space
Replay files contain:
: In some cases, the process isn't actually stuck but is performing a slow file verification. Community members suggest leaving it for at least 30 minutes to an hour if it's the first time you've seen it after a patch. All of this lives in (
You can sometimes skip this check by launching the game directly. Navigate to your StarCraft II installation folder.