Assalaamualaykum, Can a questioner do salaam to an Alim before asking any question to him?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

Greeting the Mufti with Salaam before asking the question is among the excellent acts which a person should be keen to do. A Prophetic narration is reported in this regard; it reads: "Salaam should be said before the question, and whoever asks you the question before greeting you with Salaam do not answer him." [Ibn ‘Adiyy and others]

Ibn Al-Qayyim said: “It is reported from the Prophet that he was not used to give permission to enter for someone who does not start with Salaam (while asking permission). It is also reported that he said:  “Do not give permission to enter for he who does not start with Salaam.” The best thing in this context is what is reported by At-Tirmithi that Kaladah ibn Hanbal said: “I entered upon the Prophet and I did not say Salaam and I did not seek permission to enter, so the Prophet said: “Return [go out] and say: “As-Salaamu ‘Alaykum, shall I enter?”

Finally, it should be mentioned that this is in accordance with the principal that is agreed upon, which is the excellence of spreading Salaam and the desirability of taking the initiative to say it first [before someone else says it to you].

Allaah Knows best.