SPYWARE DISGUISED AS WINDOWS WARNINGS
One common way for spyware (programs that track your internet usage, hijack your browser, and generally mess up your PC) to get installed on your computer is by tricking you into downloading it on purpose.
A common method is to pop up a window that looks like a Windows error warning. Typically it will tell you that it has discovered some problem with your computer, and gives you a button to fix the problem and one to cancel. Often, either button will download the bad stuff. So what do you do? The title bar for the window (the dark-colored area at the top) will often still say something about Internet Explorer or Firefox (your web browser), and it will always have a little "X" box to close the dialog window at the top right. Clicking the X to close the dialog is the safest way out.
It is a good idea to run a good and trusted anti-spyware program such as Microsoft's anti-spyware beta, Lavasoft’s Ad-Aware or Spybot Search-and-Destroy. Be warned that many so-called anti-spyware programs are actually spyware themselves. They may fix some problems but cause others. If you don’t already have anti-spyware software on your computer, let Brett or me know the next time one of us visits and we will install the software for you.