Search Engines not working since installing Avast

When I type in anything into Google or Bing I now get a blank page as a response. Up till a few minutes ago I was getting a warning that they had stopped a virus. What should I do?

Up till a few minutes ago I was getting a warning that [b]they[/b] had stopped a virus.
Who are they ?

Did you remove Your previous used antivirus before installing avast ?

Did you restart computer after installing avast ?

Have you run a scan with avast ?