Factory setting - New Norton?

Hello All, help or advice please.

I have Norton IS for cover of 3 pc`s which have all been allocated. Due to a malfunction on one of them, I will have to restore to factory settings, and I presume the original Norton IS will be wiped off as will most other applications.

Will I have to purchase another Norton IS to cover the re-booted pc? or is there a way to recover NIS using the existing key code?

 

Thanks in advance.