Hillary Clinton violated State Department e-mail policies and then refused to cooperate in an audit by her former agency’s inspector general, according to a scathing report issued Wednesday that undercuts her claims that her practices were “fully aboveboard.”

The inspector general found that Clinton ignored guidelines, never sought approval to conduct government business on a private e-mail server, and never demonstrated that her BlackBerry “met minimum information-security requirements.”

If she had sought approval, she would have been turned down because of clear security risks, said the 83-page audit obtained by The Post.

The report contradicted many of Clinton’s public statements that her personal e-mail use “was fully aboveboard,’ and “allowed by the State Department.”

The IG found Clinton provided tardy and “incomplete” records of her e-mails and “she did not comply with the department’s policies.”

Only this month, the Democratic presidential front-runner said she would “talk to anybody, anytime” about the e-mail issue. But Clinton declined to cooperate with the inspector general, whereas other current and former secretaries of state — John Kerry, Madeleine Albright, Colin Powell and Condoleezza Rice — all complied.

Clinton’s closest top aides — Huma Abedin, Cheryl Mills and Jake Sullivan — also refused to be interviewed.

It didn’t take long for the GOP to pounce. “She’s as crooked as they come. She got a little bad news today. Reports came down, weren’t so good. Inspector general’s report, not good,” Donald Trump said in Anaheim, Calif.

Republican National Committee Chair Reince Priebus said, “The inspector general’s findings are just the latest chapter in the long saga of Hillary Clinton’s bad judgment that broke federal rules and endangered our national security.”

Clinton’s campaign defended her conduct. “The inspector-general documents just how consistent her e-mail practices were with those of other secretaries and senior officials at the State Department who also used personal e-mail,” spokesman Brian Fallon said.

Later, on CNN, he questioned the “appropriateness” of the IG conducting a review at the same time as the Justice Department.

“We made the decision to prioritize the Justice Department review. That is going to be the last word,” Fallon said in explaining why Clinton ducked the inspector-general of her own former agency.

The IG report cites “longstanding, systemic weaknesses” in communication practices that spanned many secretaries of state. But it singled out Clinton for following her own rules.

When Abedin suggested Clinton get on State’s e-mail or make her private ­e-mail address available to the entire department, the secretary declined, saying, “I don’t want any risk of the personal being accessible.”

At least two State Department staffers expressed concerns in late 2010 to the director of the agency’s Information Resources Management about Clinton’s odd e-mail arrangement.

The IG said the staffers were told to hush up. “The director stated that the mission . . . is to support the secretary and instructed the staff never to speak of the secretary’s personal ­e-mail system again,” the IG found.

Clinton’s server was the target of several hacking attempts that she failed to report, as required. A Clinton technical advisor shut down the server on Jan. 9, 2011, because he believed “someone was trying to hack us.” Later that day, the adviser wrote, “We were attacked again so I shut [the server] down for a few min.”

The next day, a top Clinton deputy instructed staffers not to e-mail Clinton “anything sensitive.” In another incident, on May 13, 2011, Clinton’s staff believed someone was “hacking into her e-mail” after she received a suspicious message.

Department policy requires employees to report any cyber- security incidents.

But the IG said he “found no evidence that the secretary or her staff reported these incidents to computer security personnel or anyone else within the department.”

The IG also found that four unnamed top aides to Clinton used private e-mail accounts for official business but failed to turn those records over for preservation when they left office.

Those aides were not named, but their listed titles identified them as Mills, Abedin, Sullivan and former top communications and strategy aide Philippe Reines.

More than 2,000 e-mails on Clinton’s private server have been deemed by the State Department to contain classified information. And 22 have been determined to be “top secret.”