We are all using Windows 7 Enterprise x64 with Internet Explorer 11.
One set of computers -- our public kiosk computers -- has all Windows updates as of August 15, 2015. These computers use generic local user accounts with administrative rights. UAC is turned on
The other set of computers -- our employee computers -- has all Windows updates as of July 18, 2016. These computers use Active Directory user accounts that do not have administrative rights. UAC is turned on.
Both sets of computers are having the issue.
In every single case, simply adding the security certificate for the page fixes the issue.