Hello, Mr. Redstone here. I am here to discuss the problem with achievement saves on Minecraft PC. Well, I had this problem and will like the answer. You must first know the location of Minecraft on your hard drive. Open the .minecraft folder and you will see the notepad file "options". Your problem is the game reads this file and sees that the code called "showInventoryAchievementHint" will be false. you must open the file and change that setting to true by deleting "false" and typing in "true". pay attention to the format. E.g. "showInventoryAchievementHint:true" is what you should type. Do NOT touch anything else in that file. this could mess up your game.
Mr. Redstone, signing off.