Unless stated differently, Symantec maintains 60 day money back guarantee refund policy for its Norton software products. This would include Norton Security products and services.
The return policy covers new purchases and renewals. 60 day window would apply from the date of the transaction. The 60 day window is applicable to subscriptions of one year and more (i.e. 2- or 3-year subscriptions).
For monthly subscriptions and any other that are for the periods of less than a month, the return period is 30 days from the date of purchase or renewal.
Please note that shipping, handling, and any applicable tax are not refundable, except in certain states and countries where these items are refundable.
Also note that the return period or process may be different for subscription purchases sold or billed through third party vendors.
For more information about exceptions visit this support page at Norton.com: