I had no idea that a Windows Security Alert was installed on my computer. I had never seen an alert before today, which sent to running to the Windows and Microsoft support sites. I guess I figured out that it must have been installed in one of my automatic Window Updates. What scared me was this: I was reading some info on an internet page I had never visisted before and this Windows Security Alert dialog box pops up suddemly, saying I had malicious spyware and viruses on my computer and should get rid of them immediately or the computer would be harmed. Popped up behind the box was a full page of scan results. The name of the page in the upper left-hand corner said: "Online Scan". It listed in flashing red, very high numbers of infections and showed which area of the computer they were located. (My firewall is up and my antivirus and antispyware installed programs said nothing about all this). Next came a download box where they said I shoudl run their program to clean the threats. I was nervous about downloading files unknown. The only i.d. on the download thing was the address to a site named best scan 4.com I wondered why Windows would suggest such a thing. It all just didn't appear to be official Windows business to me. So I just left it. Could you please advise me on this? Is this all legitimate and shoudl I do that download and sweep?.