Best Answer: You have spyware. The best way I found to remove
it is to go to cnet.com, under DOWNLOADS.
You can get a free copy of Spybot.
It'll search your machine and create a
list of possible applications that are
causing the problem. Then you just tell it
which ones to delete.
And it's Free.
Second Best Answer: It sounds like adware. I hate starting out saying that cause that's what half the nuts say here. I would do 3 things. First, clear your temporary Internet files. You can do this typically by going to C: documents and settings, "your user name" local settings, (usually hidden. if hidden go to tools at the top of the window, folder options, click the view tab then select the option to view hidden files.) Delete the Temp and Temporary Internet files. Second, use a program that removes adware. I would recommend Checking Lavasoft.com for there Adaware SE personal. Its pretty good and free. Third, check your installed programs in the add and remove programs in control panel. If there is a search engine installed, delete it. I cant tell you which ones out of the many programs to delete, but if it has search in it, its not necessary.
Third Best Answer: You can turn off this. To do that click Preferences link(for eg. www.google.com) scroll to the bottom and uncheck the option.