Do you know DoctoAntivirus?
DoctoAntivirus is potentially an unwanted program which is promoted by free downloads or share programs from the Internet. It can be installed if users click spam email attachments or hacked web sites.
DoctoAntivirus sneaks into target computer without your notice, or even against your will. It scans your computer automatically once installed, and displays fake warnings saying that “your computer has been attacked by viruses or malware”, you need to protect your computer immediately. However, if users click “Clean Now” to fix problems, they are asked to purchase the full version of DoctoAntivirus. Never download or purchase anything provided by DoctoAntivirus, because other viruses or malware can be installed to your computer in this way.