I'd like to know if "what have you done?" can be used as a neutral question, since it is often used to express anger, shock or sadness.
For example: I want to close a window that has been opened by someone else, but it doesn't close. Can I ask the person who has opened it in a neutral, friendly way: "what have you done to my window?" or is "what have you been doing to my window?" more appropriate? Or do both sound accusatory?