Even today as there are correct Hadiths, there are fake Hadiths too; and every reader has to guard against the fake Hadiths as practising on a fake Hadith may turn hum into a Mushrik.
For example, Fazayel -e- Aamal, the bible of the Tablig Jamat, contains a story, attributed to Mohammed (pbuh) as the narrator, that Allah forgave Adam (pbuh) only when he had sought His forgiveness for the sake of Mohammed( pbuh). This story denies the Quranic ordainment that Allah is 'samad' and must be a fake invention. But still this fake story has found place in the above book and people all over the world participating the Tablig Jammat run the risk of committing shirk, tempted by the said fake Hadith, seeking Allah's forgiveness in their supplications for the sake of Muhammed (pbuh) and other good people.
There are many other fake Hadiths scholars have identified but yet in circualtion. To safeguard Islam from onslaught of various writers, it is necessary that an organised effort be taken, the OIC may come forward, to identify the fake Hadiths and compel each member country to widely publicise the same and ban books that contain fake Hadiths in their respective countries.