Live Update error

Hi,

I keep getting alert Error 8504,104  when i try to open my norton. I have downloaded and run the Norton Power Eraser Tool as instructed several times and on completion of the scan the result is always a green tick with `No Risks Found`.

However I am still unable to open the Norton main window for Live Update and the error alert re-appears.

My laptop is running good and as normal and I can use all my other programmes.

My laptop is a Asus 64- bit Windows 7 Home Basic.

I would appreciate a solution to this problem please, thank you.