Chromebook protection

I have an active account with Norton Lifelock and trying to add my daugther chrome book but I can't get it to load, keeps giving me an error?

 

Hello Alisa. The Chrome OS is a highly modified OS and proprietary making it not supported by Norton. Therefore the antivirus is not offered. There are extensions that will run which are offered in the Chrome extension store that can be used. Please review the link below.

https://chrome.google.com/webstore/search/norton

SA