After installing NIS 2012 on my Windows 7 64 bit ASUS PC, I started receiving error messages whenever I right clicked on the desktop or in Windows Explorer, instead of getting a context menu (copy...paste...etc.).
I downloaded a utility called ShellExView v1.67 - Shell Extensions Manager from http://www.nirsoft.net/utils/shexview.html which identifed all of the programs that created entries in the context menus. Since I had just instaled NIS, I disabled an extension that was identified as being installed by Symantec.
The problem immediately went away.
It appears that this is a bug that Symantec had to address and fix in NIS 2012.
I tried to attached a copy of the entry from this program, but jpg files cannot be attached.