u/NOT_AN_APPLE answered the question, “What’s the best antivirus to go on a new computer” on r/buildapc.
I work in a shop that cleans hundreds of computers a week and I see and have to deal with a lot of anti viruses. This is the general consensus on the internal forums of popular AVs.
McAfee – Literally a virus. This is the most pre-installed anti virus software out there. Common problems with this AV include the inability to access the internet through browsers, decreases in performance, especially browser performance if the McAfee extension is installed, and Operating System file corruption.
Norton – An AV good at detecting viruses with everything going against it. Norton is pretty good at scanning and removing viruses. The pros stop there. When norton expires, it deactivates it’s real time web protection which also stops your internet from working. I have seen it use more than 50% of system resources when scanning and can idle at 10%. The uninstaller rarely works on systems that have had norton on them for a while. Comes with a lot of its own adware like useless password managers and backup software. The backup software will often back up your computer to itself filling your HDD.
AVG – not very good at protecting you from viruses. Huge startup impact. Uses a fair amount of system resources. Often requires removal tool to get rid of it. Corrupts system files often. Never wants to update itself.
Avast – Has a good basic virus scanner. For some reason, more blue screen issues are caused by avast than any other anti virus. If you’re having BSOD issues or issues with drivers or programs that are unexplained, it’s usually avast.
Hitman Pro – This AV (scan and remove only) has an insane detection and removal record. If no other anti virus can fix your computer, and you really don’t want to reformat, Hitman Pro is the scanner to go with.
Malware Bytes – Very good at finding and removing browser malware and less serious malware and infections. Very good at cleaning out infections like Search Protect and Trovi. No the best at getting rid of more serious infections. Warning, this will usually delete all of your internet cookies.
Trend Micro – Causes weird issues with program installs and drivers. Real time protection can disable internet access if it screws up. If this av is causing problems it usually has to be removed with a removal tool. Not the best detection rates.
Kaspersky – Updates take forever. Huge startup impact. Very good detection with virus scanner. Pretty heavyweight and uses a lot of system resources. Worst password protector/manager ever created bundled with basic software.
Webroot – Extremely lightweight with very good detection. Uses at most 3% of your computer’s resources. Probably the only AV that doesn’t seem to cause OS or internet issues. Does not pop up asking you to buy things, doesnt come with any stupid addons. Probably my favorite AV for people who want a third party AV. Good for gamers and power users.
Windows Defender – All you really need. Since hitting “Yes” to install ShopFromHome and Search Protect on that youtube download installer will bypass any anti virus, there’s really no reason to spend money on a third party antivirus if you’re smart enough to not click on these things in the first place.
Avira – Fairly light weight AV. Probably the best free AV out there if you don’t mind xing out of the add every day. I usually install this on family computers if they’re prone to getting infections.
Editing some common questions down here…
For Macs – I would go with something lightweight since Macboook airs and the new Macbook don’t have the system resources of your typical windows computer.
Microsoft Security Essentials – See Windows defender as they are closely related.
Bitdefender – I haven’t used this AV very much at all so I can’t comment on it.
TL;DR: Free – Avira, google disable ad. Paid – Webroot all the way, especially for gamers and macs. Advanced Users can often get away with just Windows defender, maybe install and run mwb every 6-12 months.
Putting this here so I can work it into a computer maintenance/security class at some point, if the info isn’t outdated by the time I do another one.