Hi WylECyote
These are suggestions I have no idea if they will work, I have had NU15 on a vista system for over 11 months and have had no problems with it.
Top right hand side of the NU15 user interface is a tab for smart updates.
Have you tried uninstalling it restarting the computer and reinstalling it?
How did you get NU15 was it free with NIS and how many user licences is it for?
Have you had another copy of NU15 and installed one copy on one computer and another copy on the other computer and the yearly subscription has run out on the computer that needs activation so it recognises the current key but the copy is locked to the expired key which on a reboot clears the activation.
Try live chat on the keyboard it’s free, with a Norton representative on the link below. Vary the times of day you try, as it’s difficult to know when they are busy. The chat window will show the position you are in the chat cue and will pop up to the front of the pages being used on the computer when the Norton represenative is available to chat.
The Norton represenative may ask you to allow a remote access connection.
https://support.norton.com/sp/en/us/home/current/contact?directChat=on&entsrc=redirect_pubweb
ATB
intesec