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, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
Al-Haakim presented this Hadeeth in his book Al-Kuna on the authority of Abu Umaamah. It was also attributed to Abu Umaamah in Kanz Al-‘Ummaal and Al-Jaami‘ As-Sagheer. Tammaam Ar-Raazi cited it in Al-Fawaa’id with the wording: "ِA complete greeting includes taking hold of the hand"; and: "Shaking hands is to be done with the right hand. "
Imaam Ahmad cited it with a different chain of narration on the authority of Abu Umaamah with the following wording: "A complete visit to a sick person includes placing one's hand on his forehead or his hand, and asking him how he is; and a complete greeting among you includes shaking hands. " [Musnad] However, the chains of narration of both narrations are weak.
The report was transmitted as a Marfoo‘ Hadeeth (i.e. attributed to the Prophet, sallallaahu ‘alayhi wa sallam) on the authority of other companions. It has been narrated on the authority of Ibn Mas‘ood and Al-Baraa’ ibn ‘Aazib but the chains of narration of all these versions of the Hadeeth are weak and they do not corroborate one another. Al-Albaani declared these versions of the Hadeeth as weak; he commented on them after citing them in his book As-Silsilah Adh-Dha‘eefah, saying, "In brief, the chains of narration of this Hadeeth are all weak; some of which are weaker than the others and none of which can be used as sound proof. I would fairly label the Marfoo‘ version of the Hadeeth as weak and the Mawqoof (i.e. a narration attributed to a Companion) as authentic."
The authentic Mawqoof report in this regard is that which has been cited in Al-Adab Al-Mufrad by Al-Bukhari on the authority of the Companion Al-Baraa’ ibn ‘Aazib which reads: "A complete greeting includes shaking your brother's hand."
Allaah Knows best.