The issue started on June 22, when Fish released a patch intended to fix some outstanding gameplay and performance issues with Fez. That patch gave rise to new problems for some players, though, by causing their save files to appear as corrupted, in effect erasing their progress through the game.
Microsoft pulled the initial patch for the game mere hours after it first went up, to prevent the bug it contained from spreading too far. But even though Fish initially described the issue as "fairly widespread," he now says he estimates the progress-destroying problem only affects the less than one percent of players that have already completed the game (or come very close) before installing the patch."
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