I wanted to ask the proper way to respond to "thank you" ありがとう、someone recently told it to me and I did not know how to respond. I recently read that どういたしました、can be rude and is not commonly used. It can also be rude not to reply to a "thank you". Its a real conundrum!
I have seen "いいえ"、being used. If you are Japanese or if you studied and speak it what do you use for "your welcome?"
I know there is formal and informal ways of speech, I think there might be a difference here.
If I you ask me "What to say as a response to 'Thank you' in Japanese?", I shall say "It is 'iie, dou itashimashite". It literally means "I haven't done anything special", which can be an English counterpart of "Not at all".
I myself as a native speaker and a teacher/tutor of the Japanese language don't think it is rude to say "iie, dou itashimashite' at all. I mean it can be used to anyone in any case.