Shaking hands after the prayers
Imam al-Albaani (rahimahullaah) stated:
Shaking hands after the prayers is an innovation about which there is no doubt, unless it is between two people who had not met up prior to that (i.e. the prayer), in such a case it is a Sunnah.
[ Silsilah al-Sahihah (1/553) through Qamus al-Bida' (p. 410).]
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