Norton Utilities 15 - incompatible with Windows10?

After upgrading to Windows10, I updated my Norton Internet Security and it is working fine. The NIS is showing my PC as Fully Protected, in GREEN, but when I ran the Norton Utilities 15 I got an Output Message showing the Status as "LOW" in Red. Which is correct. Norton Utilities 16 is said to be compatible with windows 10 then How do I upgrade to Norton Utilities16. Please advise - Saras