More likely answer: these two computer illiterate idiots (Weiner and Huma) had no idea how cloud services work and they were using a joint account.
This would seem to confirm that she shared an account linked with her husband:
“Abedin couldn’t remember much during her time at State, according to FBI documents, including how to consistently print documents or emails from her secure Dept. of State system. Abedin told FBI agents in an April interview that she struggled to print secure docs and emails from her secure PC. Instead, she would forward the sensitive emails to:
Her personal Clinton.com email address
Her personal yahoo.com address
Her email linked to husband Anthony Weiner
Abedin said she would then access those email accounts via webmail from an unclassified computer system at the State Dept. and print the documents, many of which were classified and top secret, from the largely unprotected webmail portals. Clinton did not have a computer in her office on Mahogany Row at the State Dept. so she was not able to read timely intelligence unless it was printed out for her, Abedin said. Abedin also said Clinton could not operate the secure State Dept. fax machine installed in her Chappaqua, NY home without assistance.
Perhaps more alarming, none of the multiple FBI agents and Justice Department officials who conducted Abedin’s interview pressed her to further detail what were repeated and obvious violations of a host of federal laws.”