If your computer starts behaving strangely or displays any of the symptoms listed below, you may have spyware installed on your computer.

• I see pop-up advertisements all the time.
  
  Some spyware will bombard you with pop-up ads that are not related to a particular Web site you're visiting. These ads are often for adult or other Web sites you may find objectionable. If you see pop-up ads as soon as you turn on your computer or when you're not even browsing the Web, you may have spyware or other unwanted software on your computer.

• My settings have changed and I can't change them back to the way they were.
  
  Some spyware has the ability to change your home page or search page settings. This means that the page that opens first when you start your Internet browser or the page that appears when you select "search" may be pages that you do not recognize. Even if you know how to change these settings, you may find that they revert back every time you restart your computer.



• My Web browser contains additional components that I don't remember downloading.
  
  Spyware can add additional toolbars to your Web browser that you do not want or need. Even if you know how to remove these toolbars, they may return each time you restart your computer.



• My computer seems sluggish.
  
  Spyware are not necessarily well written programs. The resources these programs use to track your activities and deliver advertisements can slow down your computer and errors in the software can make your computer crash. If you notice a sudden increase in the number of times a certain program crashes, or if your computer is slower than normal, you may have spyware on your machine.



• Offline Symptoms.
  
  Keyboard loggers can capture passwords and user names, so if your bank or credit card accounts you access online appear to have been tampered with, your computer may be a place to start looking for clues. User names and passwords to e-mail and Web-based applications are also vulnerable.