For the record Bryan Pagliano, a former State Department employee who helped set up and maintain Hillary Rodham Clinton's private email server, has formally refused to testify to a House committee, asserting his constitutional right not to incriminate himself.
Ref: ABC News

Hillary has, indeed, done several things that are wrong.
i. She has sent and received classified e-mails, and stored them on her personal server which had not been certified as suitable for classified storage.
ii. She delivered a thumb drive containing classified e-mails to her personal lawyer for storage in his office with no consideration at all for security classification. The State Department forbids use of thumb drives for handling
any classified information.
iii. She employed her private server for
all her Official State Department email correspondence in violation of government policy as dictated by the National Archives and Records Administration, which controls record-keeping policies in federal agencies. F'rinstance all official correspondence is required to be turned over and maintained by the Department in accordance with the NARA rules when the office-holder departs. Secretary Clinton turned over NO records until more than two years after her departure, and then only because a Congressional investigation into the attack on the US Embassy in Behghazi uncovered the existence of her private server.
iv. She has repeatedly lied about the server and its contents. Secretary Clinton has said every email that could even “possibly” be work-related was turned over; the State Department has already confirmed that Clinton failed to turn over all or part of 15 work-related emails between herself and longtime confidant Sidney Blumenthal, who was sending her intelligence reports on Libya prior to the attack on Benghazi.
Ms. Clinton has been lying since she and her spouse came onto the political scene in Arkansas. Lying is no longer a matter of what she is doing it is part of what she is.