Another wretched computer scam

Using facebook last night (my monthly look-in) not only did a message flash up on screen but it was also 'talking' to me. It was coming from our old friends microsoft and at first seemed very convincing. It said I had to ring the number given within 5 minutes or everything on my computer would be lost. They would of course talk me through how to avoid it happenning (so kind). I tried to shut everything down but it was impossible. I rang my son in Spain who said to switch the computer off and also disable the router, leave it over night and scan for viruses today. Did what he suggested and it is now working as normal.
We are of course used to the 'microsoft' phone calls but this seemed to be in a different league and certainly pressed my panic button. I can imagine many people would easily fall for it so if it happens to you me son's advice works.