"If Secretary Clinton sent an e-mail about Benghazi to Abedin, Mills, or Sullivan at his or her state.gov e-mail address, or if one of them sent an e-mail to Secretary Clinton using his or her state.gov account, then State’s server presumably would have captured and stored such an e-mail.

Hillary had a private server.
Who else did?
The reasons For the unauthorized server suddenly become obvious even for the cult members.