Renewal scam

I have just been the victim of a pop-up which appeared on starting my computer.

It informs me that I need to activate my subscription following a trial.

I have not set up a trial and my subscription is not due until February 2016.  There is no way of removing the pop-up which is activated each time norton is activated.

I post this as a warning and in the hope that someone knows how to deactivate the pop-up.

Lancsgreybeard