Actionlist Not Found

I have a brand new Retina Display Macbook Pro with 10.8.3 Mt Lion running.  I am using Safari and don't have Flash installed.  When I try to install it, it gives me the error "Actionlist Not Found".  I have no other version of Flash installed and my Plug-ins Are enabled.  Why am I not able to install Flash on my laptop?

Please help.

Thanks,

Michelle