I have NIS 2013 v20.2.1.22 installed on a Win7/64 PC. Using it with Outlook 2007. The Norton Antispam Outlook Plugin (toolbar) was working properly up until just about a week ago. Suddenly the toolbar in Outlook disappeared. I can't seem to re-enable the plugin through Tools->Trust Center->Add-ins->COM Add-ins. When I attempt to do so, it simply stays on the disabled list and does not move to the enabled list.
Any ideas as to what might be causing this?