If you aren't getting a security dialogue box to set your preferences, you can do this manually. Open Norton Internet Security and then Choose the Personal Firewall option. Select Configure and the the Programs Tab. You can scroll through the list and find iTunes and QuickTime and anything else that looks Apple related. Make sure the option is Always Allow or Permit All (or something like this). If you still can't get internet access after you do this, then I recommend Removing all iTunes/QuickTime permissions. Close down iTunes before you do this. Then when you reopen it you should get the Norton security box asking you what you want to do. Make sure you select Always Allow/Permit All (or whatever it says.)