Buy an Internet pop-up window killer.  This is a software program designed to monitor the html and JavaScript code that are transferred to your computer and intercept the "windows open" command that launches pop-up ads.  When the program finds one, the command is purged before the pop-up can be displayed.  But not all pop-up windows are bad: Some crucial applications like online banking use them as well.  To make sure pop-up windows work in those cases, good software will allow pop-ups to appear when they occur as part of a secure connection, which online banking, shopping and e-mail usually provide. 

Listed below are some of the available programs which will help prevent pop-up windows:

http://toolbar.google.com/

www.adsubtract.com

www.panicware.com

www.stopzilla.com

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