JS:Decode-BTB [Trj] is a malicious cyber infection that is designed to corrupt targeted computers and benefit from victims. Most commonly JS:Decode-BTB [Trj] is promoted by some free downloads from unreliable Internet resources. Computer users may get infected with this type of infection when navigating to a malign link embedded in SPAM email or visiting compromised websites that contain the activation code of the virus. You may have no awareness of its infiltration until you see the warning popping up suddenly from the antivirus program.