Its no secret. There are lots of viruses on the web and there are lots of anti-viruses too and even lots of anti-viruses that are actual viruses. It gets messy
As an IT Pro I always recommend using some form of protection when browsing the web. The list of awesome free tools out there is long and distinguished.
I just came across a piece of very interesting information. I use a leading free product as my main AV solution and keep Windows Defender in the background. It has come in handy a few times. Now Windows Defender has an offline mode as well. In the anniversary update version you will be able to scan your drive offline. Also, it introduces Block at First Sight which reduces detection time by leveraging cloud resources for analysis. Also, and this one I really like (if it works), is the ability to block unwanted programs from installing. It has happened to us all, me included: you get so excited about a new application or are just not paying enough attention and while installing an app you forget to uncheck the boxes to install all the rest of the garbage that it suggests. Hopefully this update will help us in those moments where we forget to help ourselves
Stay clean!
EDIT: After this was originally written I read another article which has some more fantastic news for Defender. Post-anniversary it will offer lots of post-breach mitigation. I have been to a number of conferences lately and the motto is “It’s not if you will get breached, it’s what you do when you are breached”. Tools like Windows Defender Advanced threat protection offer a solution in the new cyber reality
There is a fully detailed post on the ATP functionality here: https://blogs.technet.microsoft.com/windowsitpro/2016/06/29/post-breach-detection-with-windows-defender-advanced-threat-protection/