How to tell if your computer is infected with spyware

Applies to all editions of Windows Vista

This is from Microsoft. This is posted here to avoid broken links.

Spyware is a type of software that is installed on your computer to watch and record your activity. Some types of spyware record your keystrokes and information that you type into websites or other programs and then use that information for targeted advertising or identity theft. These programs can be installed on your computer in many ways but often they are hidden inside of software such as free games, screen savers, or animated cursors.

Here are some signs that your computer might be infected with spyware:

• You notice new toolbars, links, or favorites that you did not intentionally add to your web browser.
• Your home page, mouse pointer, or search program changes unexpectedly.
• You type the address of a specific website into your web browser, but you are taken to a completely unrelated website.
• You see pop-up ads, even if your computer is not connected to the Internet.
• Your computer suddenly starts running more slowly that it usually does. Not all computer performance problems are caused by spyware, of course, but spyware can cause a noticeable change in processing speed.

Sometimes your computer will show no symptoms, even if a spyware program is running. To help protect your privacy and your computer, we recommend that you run Windows Defender or another antispyware program at all times. If you suspect your computer has been infected with spyware or viruses, you can scan your computer online with the Windows Live OneCare safety scanner.

You can also use the virus and spyware troubleshooter.