When I launch Norton 360 it is showing “you are at risk fix now” in security tab. When I click on "fix now " one more screen opens showing check for updates unable to complete . Also a screen showing "fix not complete "is displayed. I have attached all the screenshots for reference.
I have the very same issue with Norton 360 on Mac OSX 10.14.6. I keep getting "Fix this issue. Your vulnerability protection definitions are not up to date. Your Mac may be at risk". It does not matter how many times I run the fix now, which tries to update definitions, it always ends up returning to the same error.
And are you restarting your system. Not shutdown and startup again if you have Windows Fast Startup feature enabled. If you use Windows 8/8.1 or 10, there can be an issue with the Windows Fast Startup feature.. See more information here.
Start by restarting your computer then try the LiveUpdate again. This can just be a temporary server error between your computer and the LiveUpdate servers.