I have Norton 360 Premier edition and for several weeks I have been getting the "8506, 421" error message.
Norton 360 will not initialise and the splash screen will not come up.
Instead I just get this error message all the time.
I have downloaded and used both the removal tool and norton power eraser and I still get the error 8506, 421 message.
I have been a solid user of Norton for several years but I am considering leaving them now,
as this is extremely frustrating, annoying and a major inconvenience!!
any ideas how to get rid of this pesky error message permanently would be most welcome.