She knowingly sent, received, and stored classified information on a unsecured private server.

18 U.S. Code § 798 - Disclosure of classified information

(a) Whoever knowingly and willfully communicates, furnishes, transmits, or otherwise makes available to an unauthorized person, or publishes, or uses in any manner prejudicial to the safety or interest of the United States or for the benefit of any foreign government to the detriment of the United States any classified information—

(1) concerning the nature, preparation, or use of any code, cipher, or cryptographic system of the United States or any foreign government; or

(2) concerning the design, construction, use, maintenance, or repair of any device, apparatus, or appliance used or prepared or planned for use by the United States or any foreign government for cryptographic or communication intelligence purposes; or

(3) concerning the communication intelligence activities of the United States or any foreign government; or

(4) obtained by the processes of communication intelligence from the communications of any foreign government, knowing the same to have been obtained by such processes—

Shall be fined under this title or imprisoned not more than ten years, or both