There are still records out there. You don’t just erase email communications, even though some believe that you can.
IF the clintonemail.com server had other email accounts set up on it and none of her respondents used their government emails to contact her, except through THEIR private clintonemail.com accounts, exactly where would this “out there be?”
I’ll tell you. Not on government servers unless they keylog every computer or record every data stream 24/7. The evidence would be on her computer/server...in her home.