Why does Internet Explorer suddenly, for no reason, start opening new tabs? (Hundreds even, until I

I'll be browsing with IE7, and after clicking a link, even within a reputable website, multiple tabs will start opening up, one after another, rapid-fire (IE6 did the same thing, opening new windows, rather than tabs). It won't stop until I use Task Manager (ctrl+alt+del) to end task. Sometimes hundreds of them will open. I keep my anti-virus, anti-spyware, firewall and Windows up to date and run scans regularly, but it continues to happen. I've searched the web, including Microsoft, for answers, but have found no help. Has anyone else experienced this? Why is it happening? What can I do about it?

Why does Internet Explorer suddenly, for no reason, start opening new tabs? (Hundreds even, until I end task)?live update

You have smalware installed on your system. If you follow all the following steps it should get rid of your problem and prevent future problems. All programs listed are free.

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Update your antivirus and run a full scan

If you do not have virus protection install:

AVG Antivirus 7.5 Free Edition

http://free.grisoft.com/freeweb.php/doc/...

or

Free antivirus - avast! 4 Home Edition

http://www.avast.com/eng/avast_4_home.ht...

or

AOL Active Virus Shield

http://www.activevirusshield.com/antivir...