Taking a family name other than that of one’s father (or attributing oneself to someone other than one’s father)
Question

A woman before becoming Muslim changed her last name from her family name to her husband's. Now that she is Muslim, she is no longer married to that man. Also, she would like to formally change her name to a Muslim name to affirm her Islamic identity. She would like to also change her last name back to her family name, however, she would like to adopt her mother's maiden name (maternal grand-father's name) instead of her father's name, since there is some conflict between them, and that she said he did not have much to do with her upbringing. Is it permissible for her to take her mother's maiden name?
Praise be to Allah.This womans desire to take an Islamic name and to change her family name from that of her former husband is quite correct, but it is not permissible for her to call herself after anyone except her legitimate father no matter what the reasons for wishing to do so. Allaah says (interpretation of the meaning): "Call them (adopted sons) by the names of their fathers" [al-Ahzaab 33:5].
The Prophet (peace and blessings of Allaah be upon him) said: "Whoever calls himself by other than his fathers name (or attributes himself to someone other than his father), will be cursed by Allaah, the angels and all the people." (Reported by Ibn Maajah, 2599; see also Saheeh al-Jaami, 6104).
And Allaah is the Source of help.