The Metal Gear Solid V bug that corrupts your save file if you bring companion character Quiet on two specific missions now has a workaround to bridge the time before Konami releases a proper patch to fix it.
The message on how to avoid the problem should show up when you start the game, but Konami has also detailed it on its website. To keep your save intact after missions 29 or 42 with Quiet, you need to either use the Butterfly Emblem throughout the missions or never raise your bond level with her to its max level during them. Or you could just bench her for those two missions to play it completely safe, but that’s up to you.
Konami says it’ll release a patch for Metal Gear Solid V on all platforms that should fix the problem and the affected save files soon, but hasn’t given any more of a specific time frame than that.