Fixing the Hosts File and Running the Scans
In some cases, the browser is redirected to unwanted website. To fix this problem, ensure the Windows Hosts file has not been modified, but to make sure that you have the default Hosts file, execute the Microsoft Fix it 52067 to reset the Hosts file.
Proceed to running a scan using any of the following malware scanner and remover programs that you have downloaded and stored in the flash drive or saved on the desktop: SUPERAntiSpyware Portable, Windows Malicious Software Removal Tool, A-squared Free or Malwarebytes’ Anti-Malware. Allow the scanner to remove the detected objects. Note that it is not necessary to run a full system scan. The said malware scanner and remover programs are providing a quick scan with the ability to scan the locations where the malware is known to hide or install.
Reboot the computer then run another scan until the scanner reports that the computer is clean from any infection. It is a good idea to run a scan using several malware scanners because there's no single antimalware program is capable to finding all kind of infections. Try scanning the computer using the other scanners that you've downloaded and again, allow the scanner to disinfect the PC.
Verify that the computer is not infected by a rootkit, scan the computer using a standalone rootkit scanner and remover e.g. Avira AntiRootkit Tool, Sophos Anti-Rootkit, Panda Anti-Rootkit, or F-Secure Blacklight.
Install CCleaner to clean-up the system and Internet files. To prevent being infected again, keep your programs up-to-date. If the Windows spyware warning messages continue to appear, you should proceed to visiting a malware removal forum offering removal assistance by some volunteers.