Is your computer suddenly running sluggish, and unknown toolbars and pop-ups have started appearing everywhere. Microsoft Safety Scanner to the rescue! This portable anti-malware utility requires no installation, meaning it can run from a flash drive — a mighty handy option for troubleshooting a PC that’s so bug-ridden, it can’t even get online.

Thanks Microsoft for offering users a free, portable anti-malware solution, I think most folks are better off with something like
Malwarebytes Anti-Malware

SuperAntiSpyware