Adware

Advertising software (adware) on your computer can cause multiple pop-up advertising windows to appear on your screen and can often reduce the overall stability of your system. “Spyware” is a form of adware that can collect information about web sites you visit and key strokes you type.

Most adware is installed without your knowledge, through certain web sites that prompt you to install special software in order to view the page (see Browser Hijacking). 

Some adware purport to be useful and some even have real functionality. This functionality must be weighed against the problems you may encounter when you have it installed. The problems may be enhanced when more than one adware program is present at the same time.

 Be Cautious

Some websites, upon your initial visit, ask you to install software that extends the functionality of your web browser. For example, windowsupdate.com prompts you to install a piece of software that lets the browser check whether your copy of Windows has the latest security patches (this one is legitimate). However, some not-so-reputable websites use this technique to maliciously install adware and spyware on your computer.

 If you are not sure about a specific piece of software you are being asked to install, you should cancel the process and search the Internet for more information to help make your decision. 

 If you are prompted to install software you don’t recognize and don’t want to install — be cautious. Even when you select “Cancel” or “No” in these windows it may install software without your consent. The best way to dismiss these prompts is to click the “X” in the upper right side of the window. If you think you may have made the wrong choice when prompted in the past, please read “detecting adware” below.

 Detecting Adware

One way to rid yourself of advertising annoyances is to install and run software that detects and deletes advertising programs. One such program is MalwareBytes.