Problem installing Norton 2012

I downloaded Norton 2012 but it would not open on my computer.

 

At first I got an error message...Error 8504, 104. The fix for this was supposed to be by downloading the Norton Power Eraser and running it.

 

I downloaded it to my desktop but when I tried to run it I got a message that said it was not a file approved to run on my Win XP system.

 

I don't know what to do now.

 

Please help

 

Ron