LiveUpdate Doesn't Complete When I Run It

I have latest version of Norton Security Deluxe on a 2014 iMac, and the 2015 12" Retina MacBook.  Both are running OS X  10.11.4.

It seems to be updating itself, but, if I click on the LiveUpdate button, it runs for about 5 minutes, then halts with "LiveUpdate could not complete." message.

What do I need to do to correct, or GET it corrected.

Thanks.