What is prescribed regarding greeting non-Muslims?

Question:
Regarding greeting a non-Muslim for the sake of da'wah: is it to be done with the prescribed formula...?

Answer:
Do not initiate it; do not greet him first.
Q: Even for the sake of da'wah?
A: Do not greet him first. The Prophet (peace and blessings be upon him) said: , and the polytheist is more severe in disbelief than they are.
Q: What if it is not with the prescribed formula?
A: "How are you?" or "How are you doing?" is not called a salam, or "How are your children?" or "How are you, so-and-so," and then he invites him to Allah. There is no contradiction; this is not a salam.
Q: "Good evening," "Good morning," "May Allah bless you with goodness"?
A: He says: "How are you?" or "How are you doing?" He does not say: "As-salamu alaykum."
Q: What about saying: "May Allah bless you with goodness"?
A: It is easy; it is not a salam. So if he sees benefit in doing so, he does it.
Q: Could "May Allah bless you with goodness" be a supplication for him?
A: It is a supplication, yes, but it is not a salam.
Q: Is there no harm in it?
A: If he sees benefit in doing so; because the salam is "As-salamu alaykum."