I recommend trying Unthreat Antivirus, it's not as well known as the other ones but after doing quite a bit of research I decided to try Unthreat and I couldn't be happier, it doesn't slow down my computer while scanning which is great. I totally recommend it.
My shops make a LOT of money from people who use FREE Antivirus software, when they come into my shops WITH free software AND VIRUSES...lol
All the best Brett
Those people usually aren't very bright. I've used free antivirus software for years. My computer is still running strong...as is every computer that I've ever installed free antivirus software on.
Norton is a resource hog. There are plenty of free, light-weight antivirus programs out there that do a great job.
@OP
Microsoft Security Essentials is an excellent antivirus program. Like others have stated before, I use it in conjunction with Malwarebytes Antimalware. I'll link you to both. Here lately, I've been researching other free programs, but haven't really found any I like. Here's links to both programs...
http://www.tomshardware.com/news/AV-TEST-Certification-Security-Essentials-Double-Failure-0-Day,20524.html < MSE FAILS 2 YEARS IN A ROW
Norton is a resource hog < NOT IN THE LAST 3 YEARS
Never had a problem with MSE. Worked fine for me and has caught everything I've thrown at it. Although, it has caught a false positive before. However, that was due to a torrent. The best fool proof antivirus is common sense. Don't open emails from people you don't know. Don't go to sites or download from sites that your aren't familiar with or aren't credible. It's simple.
Any proof to back up Norton? Besides, the OP wants a free solution. Not some program that you pay to hold your hand.
@OP
Those other programs I listed are still viable options. In the meantime, I'll be researching more programs.
Hm, so far the only programs I'm liking are Avira and AVG. I would still highly suggest you use whichever antivirus you choose in conjunction with a malware cleaner such as Malwarebytes.
I recommend MSE, have been using it for years, no problems. recently removed ransomware off friends computer which had paid Norton on it. Norton is a resource hog is an under statement. 😀