I have two answers for you, my answer and then the one that you want?
My answer is get an anti virus. There are many free ones out there that are very good. It does not have to be MSE. I hope you do not think that I am out of line, but I treat every member that I help like a friend, trying, only to do the best for them.
The second answer is from one of our fine tutorials: Windows Defender Notification
=Security System Tools
I hope that you choose my first option.
If not, I hope that the tutorial works for you. And that you have happy and safe surfing.