Friends with classified clearances have told me that these servers are in a closed system AND they are in a walled off room inside the outer walls of the building.
To gain access, two people must got in at the same time. There are multiple security codes that must be used to simply access the room.
Putting a USB drive into the server sets off a loud alarm!
The classified email servers are in a closed system. No email from that closed system is allowed to leave the system!
IOW, with Hillary likely to receive emails from hundreds of ambassadors a day that were supposed to be part of the closed system, she likely committed scores of felonies each and every day.
Her criminal liability would be in excess of 100,000 years in prison for all of the felonies she committed.