Guidance from The Prophet (peace be upon him)
Hadrat Abu Hurairah (r.a.) reported: The Messenger of Allah (peace be upon him) said, "When one dies, all of ones deeds come to an end except for three things:
1. Sadaqah Jariyah (ceaseless charity);
2. Ilm-unn Nafeh (knowledge which is beneficial), and,
3. a virtuous off-spring who supplicates for them (the deceased).
Related by Muslim.
Deeds (good or bad) are added to ones Book of Records with Allah Subhanah only as long as one is alive. As soon as one breathes ones last, absolutely no addition or subtraction can be done in ones Book of Records except for the three acts which are listed above:
continuous act of charity: ie. the charity done by the deceased (in his lifetime) like building a school, or a hospital, or a mosque, or a well, etc. which is still being utilized for the good of man even after his death
.the deceased shall earn a reward for such continuous deeds of charity even after his/her death.
beneficial knowledge: ie. if the deceased strove and exhorted someone to believe and obey their Lord Creator, or the deceased gave someone a copy of the Glorious Quran, or some good advice, etc
.then he/she will continue to receive the rewards of every good that person did on his/her advice.
righteous offspring: ie. the near and loved ones who constantly supplicate their Lord to forgive their deceased loved one.
In light of the above quoted authentic narration, all the other innovated rituals which some ignorant amongst the living do for the deceased like qull, fatihah, niyaaz, etc. do not benefit the deceased in the least!