What is the authenticity of the content included in the book *Al-Du'a al-Mustajab*?

Question:
These are several questions from the female listener (M. H. A.) from Makkah al-Mukarramah. Her first question is: There are some books specifically dealing with the dhikr and supplications narrated from the Messenger of Allah (peace and blessings be upon him), such as the book *Al-Du'a al-Mustajab*. I found in it supplications for each day of the week; there are supplications and dhikr for Friday, and others for Saturday, and so on. Is adhering to these dhikr a religious innovation, or is it part of the Sunnah?

Answer:
This is an unapproved book, and its author is a night gatherer, collecting the chaff and the grain, the authentic and the weak and the fabricated. Therefore, it is not relied upon, and it is not permissible to designate any day or any night with anything except with evidence from the Infallible one (peace and blessings be upon him).
So this book is not relied upon, but you should review the other books. What is established from the Messenger of Allah (peace and blessings be upon him) regarding the dhikr of the morning or the evening, or supplications to be recited in the morning or the evening, that is prescribed, and what is not, is not.
As for this book, which is *Al-Du'a al-Mustajab*, it is not relied upon; because its author is not qualified for that; and because it mixes the chaff and the grain, the authentic and the weak and the fabricated. So this book is not relied upon, yes.