Your browser might be hijacked. First, scan the system for parasites and
remove them. SpyBot S&D searches your harddisk for Spyware and Adware http://security.kolla.de/
This will remove malware from the PC. Next, reset the Search Engine. Click
the Search button in the toolbar > Customize > AutoSearch Settings > Select
a provider from the list.
Open Internet Explorer > Tools > Options > Programs > "Reset Web Settings"