What, if any, antivirus is/was he using?
If none, Malwarebytes is not an antivirus
Malwarebytes Anti-Malware is not meant to be a replacement for antivirus software. Malwarebytes Anti-Malware is a complementary but essential program which detects and removes zero-day malware and "Malware in the Wild".
As for the "best" antivirus, everyone has his/her own opinion.
There is no size fits all when it comes to internet security. Sometimes a program won't play nice with a system. What works for one person may not work for you. I've tried security programs that made my computer crawl slower than a turtle. One of them made the computer so slow I could not get to add remove programs to get rid of it. I ended up reinstalling Windows to make it go away.
For the past 2 or 3 years I've been using Eset Smart Security (for purchase program). It works well for us.
Do you want a free program or do you want to purchase one? If free, there are some good ones available. You might have to try several of them to find the one that works best for you.
Do you want only an antivirus or a suite that includes a firewall?
IF you decide to purchase an antivirus or security suite do this first:
Go to the website of the program. See if it has a free trial-most of the major products do. Install the free trial on all computers (only if you there is an option for multiple license if you want to possibly use it on all computers). This will give you a chance to see if it works well with each system and if it is user friendly. Trial versions are fully functional.
You would not want to find out that it doesn't play nice with one of the computers after your buy the product.
Sometimes there is a bonus when using trials: if you give them your email address they may send you special offer close to the end of the trial. Also be aware that you may get a "purchase nag" screen which is worth putting up with in order to find out if works for you.
Free programs may also have a nag screen meant to entice you into upgrading to a paid version of the program.
I urge you to read this which may help you decide which product to use Choosing an Anti-Virus Program
It includes a list of free programs.
Whatever you do you can keep Malwarebytes and he can continue to scan with it when he runs a virus scan.
Malwarebytes is an excellent program but it has to be used in addition to an antivirus.
Edited by Queen-Evie, 26 September 2014 - 12:12 PM.