Education Secretary Betsy DeVos has on occasion conducted government business through her personal email accounts, and she hasn’t always saved the messages properly, federal investigators said in a report released Monday.

According to the Education Department’s Office of Inspector General, the agency’s email system revealed a “limited” number of such communications that had been sent or received by DeVos’ personal accounts. These government-related messages had not been directed on to her department accounts, but did appear in the government accounts of other department staffers who were included on the emails.

In total, investigators found fewer than 100 such messages sent to or from DeVos’ four personal accounts between Jan. 20, 2017, and April 10, 2018.

“Most messages occurred during the first 6 months of 2017 and were from a single writer who was offering advice on potential candidates for Department positions,” the report read. Other messages were from individuals offering DeVos their congratulations on her confirmation to her new position along with advice.

During that same period, DeVos used her personal accounts to send six messages to a department email address, five of which concerned official business.

The investigation determined that “the Secretary’s emails related to government business were not always being properly preserved.”

The report noted that DeVos has been personally briefed on “records management requirements,” including a warning that “employees are prohibited from using personal email or messaging accounts to conduct official government business.”

The investigation was completed per a 2017 request from House Democrats.

President Donald Trump turned the use of private email servers into a rallying cry for his 2016 campaign, attacking Democratic opponent Hillary Clinton for having used private servers to conduct government business while she was secretary of state. However, a federal investigation into the issue found that Clinton committed no crimes and did not intentionally mishandle classified information.