This update upgraded to a new version of unity 3d, and apparently norton didn't like that in your case, and corrupted it in some manner. If you look in your runtimedata/updates folder you should see a zip file for 4.032: if you manually unzip that into your game folder, it should have everything you need to get it working. You can also try running the updater directly from the install folder, and it will unpack that zip file for you in an automated fashion. As long as norton isn't allowed to interfere, that should work. At present, it sounds like it prevented about half the files from beig unpacked, but they're all sitting there on your computer in that 4032.zip file in runtimedata/updates.
Hope that helps!