When someone thanks you, the courteous and polite reply is, “You’re welcome.” The meaning implies that it was a pleasure for you to help the person, and that you receive their appreciation. Though the casual laid-back phrase, ‘no problem’ may intend to communicate this, it falls short. It actually negates the person’s appreciation and implies the situation could have been a problem under other circumstances. In business situations, if you want to be perceived as well-mannered and considerate, respond to thank you’s with, “You’re welcome.” – Forbes