I think You Should post your problem of Norton 360 in the Norton Forum(community.norton.com)
Do these After You Get your System Fixed..................
Not Now or you will end up in a really bad situation
I have Tried Norton Antivirus/Internet Security IMO only i think Its extremely light It did not slow down my Lappy
you should defragment your Harddisk and remove temporary files to see if their is any improvement in performance
avoid unnecessary start up item like AdobeARM and plenty of others
BTW Norton was much Lighter than Kaspersky and BitDefender.....
But The lightest has to be Eset Smart Security Its lighter than Microsoft Security Essentials and Avast or any other AV I have tried out........
Just thought you may know when I had MSE Installed it took quite a while to load my Visual Studio Projects and my Net Beans to start up but with Norton it reduced
with Eset even more
Try 2 or 3 AV`s before you purchase
Norton 360 `s protection components are not superior to the Internet Security / Antivirus(Has no Firewall but everything else is the Same)
I don`t have a fast Laptop just the Usual Core i3 with 4 GB Ram..........................