You can download Adaware 2007 free from here
http://tinyurl.com/du0h
Spy Bot S & D free from here
http://tinyurl.com/yrwy2
Install both of these update them and then reboot into Safe Mode and Scan the System with each program till they come up clean. Remove any Infections found and then reboot and see if the problem persists. If you are unable to remove some infections chose the Scan on Reboot Option in Spy Bot and try to remove everything.
Most of these Hijacks of IE can be put down to accepting what appears to be a Free Offer advertised on the Internet which infects the computer. Some require you to almost wipe the HDD and reload to remove.
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