I also got that message. It came from your AV AVAST. It doesnt mean you need to do anything necessarily, the message would have gone to everyone using AVAST regardless. Do you use Internet Explorer as your browser ?
One of the Techies will be able to help you find which version you are on if you do.
Download Google Chrome as your browser (it's free). You will be amazed at the difference. This will in no way prevent you from "getting a man in" if you are so inclined!!
You should be able to go to the Microsoft website and look for and download/install their latest version Internet Explorer. Or you could simply forsake it and choose one of those recommended to you by some other browser supplier, as suggested by others here.