Having an installed antivirus on a computer is a good solution, but if the user does not know the basics of security on the Internet, then the antivirus may not be a panacea.
If you can want use any antivirus you can try full package or full version with 'Internet security facilities' antivirus,So I thing solved maximum security problem, but it is depend your antivirus company.
Even that wouldn't work, every time a anti-virus would detect something the user still has the authority to give permissions. For example a website is blocked by your anti-virus users could still give exceptions to still continue visit the website and maybe download a malicious software. At the end users are still at fault as they risk themselves on allowing exceptions. Still users need to have proper internet knowledge when it comes to scams, phishing, and malicious softwares as even anti-virus does not guarantee your computer's protection from your own wrongdoing.
You must have basic knowledge of using a computer and browsing the internet, If you do not know how to use them like crazy then any kind of problem can happen at any time, It depends on your usage How do you use it, An antivirus will not have to solve all your problems, And none of the software in the world has yet to make any problem that will solve all the problems, A program can only help you, it can not do all your work, An antivirus and the right ones will some help you.
