All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
Al-Qaadhi 'Iyaadh narrated the story in question in Ash-Shifaa’, where Aadam supplicated to Allaah The Almighty through the status of the Prophet in the sight of His Lord. Scholars of Hadeeth classified this Hadeeth as Dha‘eef (weak), thus it cannot be used as evidence to support the permissibility of making Tawassul through the status of the Prophet Muhammad .
In fact, scholars differ on the ruling about making Tawassul through the Prophet himself, his status or his right. Most of the Maaliki, Shaafi‘i and Hanbali scholars of Fiqh (jurisprudence) are of the opinion that it is permissible. They supported this opinion with Hadeeths that cannot stand as evidence, though, as they are either weak or fabricated. They also supported their opinion using texts of general meaning from the Quran and Saheeh (authentic) Hadeeths that are not clear evidence for the permissibility of this type of Tawassul.
On the other hand, scholars who objected to this type of Tawassul have relied on the fact that there is no clear and authentic text to permit it. Moreover, the status and the high rank of the Prophet are not the result of one’s own deeds. Allaah The Almighty Says (what means): {And that there is not for man except that [good] for which he strives.} [Quran 53:39] Their evidence for prohibiting this type of Tawassul includes that it is a means of seeking relief or benefit from other than Allaah The Almighty, which may, in turn, lead to Shirk (polytheism).
Moreover, the Prophet the Companions and their successors did not guide us to do this.
Thus, the second opinion is the predominant one due to the solid evidence given by its proponents and due to the fact that Tawassul is a type of supplication, and supplication is an act of worship - whose performance may be sanctioned only by the Quran and Sunnah.
Allaah Knows best.