What is Ibn Uthaymeen's view on the ruling regarding the exchange of greetings (saying and returning "Salam") between women and men? Is it disliked (makruh), contrary to what is better (khilaf al-awla), or forbidden (haram) if it is not between acquaintances or over the phone as needed?

Shaykh Ibn Uthaymeen states that it is impermissible for men to greet women, or women to greet men who are not their mahram, except when there is no fear of fitnah (temptation). Exceptions to this include greetings during phone calls, to the extent of need, or if the woman is known to him. However, greeting a woman in the marketplace is not permissible because it is a great source of fitnah. Al-Bukhari mentioned a chapter titled "Men greeting women and women greeting men," and Ibn Hajar explained that its permissibility is contingent upon the absence of fitnah.