OK, this is strange. Last night my NIS 2012 ran it's monthly full system scan. Imagine my surprise this morning when I found that it had detected 66 high-risk "threats". The strange thing is, these were all payware software exe files from big-name companies that I have bought and downloaded over the years. Many have been on my hard drive for 4 or 5 years, and never been flagged until now. Some were downloaded with NIS 2010-2011-2012 running, and were verified at the time to be safe.
A few examples are: several versions of Acronis True Image; an old version of Nero DVD writing software; an HP printer driver; Google Earth, and several others. Most of these were on a non-system HD that I use for storing payware, but a few were in my c:windows\installer and c:program files (x86) folders. BTW, I'm running Windows 7 64-bit.