How to Get Rid of Yahoo! Search Redirects
If you type a website address into Yahoo! and your browser is directed to a completely unrelated website, your computer is probably infected with a type of malicious software known as a "browser hijacker," also called a "redirect virus." Browser hijackers redirect your Internet searches to other websites maintained by hackers and may change your Internet homepage as well. Several free anti-malware programs are available that can remove browser hijackers. You will need to download and install one of these free apps on your computer to repair the browser redirect problem.
Microsoft Security Essentials
Launch the "Microsoft Security Essentials" application on your computer.
Click the "Home" tab in the application's main window.
Check the box next to "Full" under "Scan Options."
Click "Scan Now." The application will scan your entire computer and remove any browser hijackers that it detects.
AVG Anti-Virus Free Edition 2011
Open AVG Anti-Virus Free Edition 2011.
Click "Computer Scanner" in the left pane of the application's main menu.
Click "Whole Computer Scan." AVG Free Antivirus 2011 scans your entire computer. This could take from a few minutes to several hours, depending on the size of your hard drive and how much data is stored on it.
Click "History" at the top of the main menu and select "Virus Vault" when the scan is complete. The Virus Vault window opens.
Check the box next to each malicious program that you want to delete, then click "Delete."
Avira AntiVir Personal Free Antivirus
Launch the Avira AntiVir Personal Free Antivirus application.
Click "Local Protection" in the left pane of the main menu, then click "Scan."
Click the "Magnifying glass" icon with the red, green, blue and yellow Windows icon. Avira AntiVir Personal Free Antivirus will scan your computer and remove any browser hijacking malware that it detects.