My name is Mansoor Lakhani. I was born in Pakistan to a Sunni Lakhani family. I know there are lot of Islameeli Lakhanis in Pakistan, but we are not related to them in anyway.
Anyway, according to my grandfather my ancestors who resided in India shared the last name of Lakhan. Then some Saint from Persia moved to India and converted many followers of Hinduism to Islam. Those members of the Lakhan family that converted changed their last name to Lakhani to distinguish themselves from those who did not convert. Well, ours was the family that converted and that is why we ended up with this last name "Lakhani".