One misconception of Ibn Taymiya has disrupted the Muslim community. He condemned tawassul and istighasa (asking for help) through the Prophet(PBUH). No one of the ulama ever stated a similar opinion.
Actually Ibn Taymiya was wrong affirming that tawassul and istighasa were not permitted. There was no alim thinking this way except for him. Quite the contrary, tawassul through the Prophet(PBUH) is a hasan (a good deed). No matter when is it used - before or after the creation of the Prophet (PBUH), during his life or after his death.