1) Power up your computer, and press and hold down the F8 key. You must do this before the Windows logo appears. This will take you into Safe Mode. Select Safe Mode with networking from that screen.
2) Uninstall any anti-virus program you now have installed.
3) Download BitDefender (anti-virus), and run it. http/www.bitdefender.com/solutions/free.html
4) Download Malwarebytes and run it.
5) Download and run CCleaner. http/www.piriform.com/ccleaner/download
6) Shutdown and restart.