Have you updated your anti-virus protection lately? Always a good idea. AVG is a good free version to take care of that computer of yours. They have just released the latest major update, version 9.0. Free is good.
Click here to download and install.
Editor’s note: You’ll get a message during the install to choose between the “full” protection and “basic” – if you want the free version, choose “basic”. Otherwise, it will expire in 30 days when the trial period is over. Lastly, choose “custom” install – so you can tell it to skip the “Toolbar” installation. It’s worth the effort.