Message that SAMSUNG sm n920a is infected with dangerous Trojan horse

[AC Question]

What do I do

 

[belodion]

First, tell us the origin of the message. It may be a lie. A screenshot of it might help.

 

[B. Diddy]

Welcome to Android Central! If it's a popup that occurs only when you're browsing, then I agree with belodion -- it's a fake warning associated with that website, designed to lure you into installing a fake "antivirus" app that is probably malicious itself. Avoid that website.