Avast Free Antivirus keeps shutting down

I have installed the free Anti-virus program (more than once). But it does not stay on. It said it was installed and the computer was re-started. But a few minutes later, a red flag appears at the bottom of the desktop, saying I should turn on and update Avast Antivirus. I click on it, and nothing happens. I click on the box that says I trust this program’s publisher, and still nothing happens. This is extremely frustrating and I don’t know what is wrong. If anyone has simple, easy-to-understand advice, please reply. Thanks.

  • Which version/build of Avast Free…?
  • OS…? (32/64 Bit…? - which SP/Build…?)
  • Other security related software installed…?
  • Which AV(s) did you use before Avast…?

Successfully Install Avast http://goo.gl/VLXde