Try resetting the home page as shown in the [[how to set the home page]] article. It is also likely to have changed the location bar search settings. # Type '''about:config''' into the location bar and press enter # Accept the warning message that appears, you will be taken to a list of preferences # In the filter box type '''keyword''' # Right-click on the preference '''keyword.URL''' and choose ''''Reset''' to change it back to Google. If these changes do not stick when you restart Firefox, follow the procedures in the [[Preferences are not saved]] article. To be sure that no malware has been installed, try running several malware scanners. It is best to run several as each will pick up things that the others miss. Some scanners you can try are: * [http://www.malwarebytes.org/mbam.php Malwarebytes] * [http://www.superantispyware.com/ SUPERAntiSpyware] * [http://www.lavasoft.com/products/ad_aware_free.php Ad-Aware] * [http://www.microsoft.com/windows/products/winfamily/defender/default.mspx Windows Defender] * [http://www.safer-networking.org/en/home/index.html Spybot S&D]