Since two days I am trying to update my L640XL to 10586.218 but each time it's saying some kind of error which says update data is corrupted blah blah blah... I found solution for this error, and it's not worthy for me. It saying, either do soft reset or hard reset. Obviously soft reset doesn't solves this issue anymore (tried 7-8 times) and i don't wanna hard reset. Also there was another solution. Changing language, region or speech settings forces phone to update and rebuild the phone update. But this one also not working. Formatting phone and after installing new update as well as apps is too boring and time consuming. Also I don't wanna lose app data. Is there another solution?