Hillary Clinton disregarded various State Department guidelines for avoiding cybersecurity risks, an internal audit found Wednesday, faulting her and past secretaries of state for weak information management.

And she failed to report numerous attempted hacker intrusions into a private email server she maintained at her home.

Despite guidelines to the contrary and never seeking approval, Clinton used mobile devices to conduct official business on her personal email account and on that private server, a 78-page analysis from the department's inspector general concluded.

She never sought approval from senior information officers, who would have refused the request because of security risks, the audit said.

And her most senior aides refused to meet with investigators who were looking into why.

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TROUBLE: Former Secretary of State Hillary Clinton went around established cybersecurity procedures and never sought approval for her private email setup, an inspector general report says

PILING ON: Donald Trump said during a New Mexico rally on Tuesday night that Clinton 'is as crooked as you get, believe me,' referring to the growing classified email scandal swirling around the former secretary of state

The report spells out the aftermath of a 2011 hack attack, when an IT staffer shut down her server for a few minutes in the hope that the problem would go away.

But he quickly warned Clinton's most senior aides not to send her 'anything sensitive.'

After another hacking attempt, Clinton told colleagues that she was afraid to open emails.Still, she never reported the attempted breaches to computer security experts at the State Department.

'Notification is required when a user suspects compromise of, among other things, a personally owned device containing personally identifiable information,' the Office of Inspector General wrote.

'However, OIG found no evidence that the Secretary or her staff reported these incidents to computer security personnel or anyone else within the Department.'

The independent watchdog report also said Clinton, as the top official at the State Department, was responsible for printing and saving her official emails – or at least surrendering her work-related correspondence when she left the position in February 2013.

It took 22 months for her to hand over her emails, after she deleted tens of thousands that she and her lawyer deemed 'personal' in nature.

'Secretary Clinton should have preserved any Federal records she created and received on her personal account by printing and filing those records with the related files in the Office of the Secretary,' the report declared.

'At a minimum, Secretary Clinton should have surrendered all emails dealing with Department business before leaving government service and, because she did not do so, she did not comply with the Department’s policies that were implemented in accordance with the Federal Records Act.'

The inspector general, who serves as the State Department's independent internal watchdog, wrote that a senior Clinton aide was warned in 2010 that existing systems might not be capable of preserving documents as federal law requires.

But the aide dismissed those concerns and suggested that they were legally sufficient.

UH OH: The Inspector General report found that Clinton's three top aides stonewalled investigators and refused to meet with them for interviews

The IG, however, could find no evidence that lawyers had reviewed Clinton's document-retention procedures to make sure the law was followed.

Clinton, along with her top deputies Cheryl Mills, Jake Sullivan, and Huma Abedin, all refused to meet with investigators from the Inspector General office, the report's authors complained.

They also cited 'longstanding, systemic weaknesses' related to the agency's communications.

These started before Clinton's appointment as secretary of state, but her failures were singled out as more serious.

'By Secretary Clinton's tenure, the department's guidance was considerably more detailed and more sophisticated,' it concluded.

'Secretary Clinton's cybersecurity practices accordingly must be evaluated in light of these more comprehensive directives.'

The review was prompted by the revelations of Clinton's email use, which has affected her campaign for the Democratic presidential nomination.

Nevertheless, the review also encompassed the email and information practices of the last five secretaries.

The report said the department and its secretaries were 'slow to recognize and to manage effectively the legal requirements and cybersecurity risks associated with electronic data communications, particularly as those risks pertain to its most senior leadership.'

Clinton has been dogged by questions about her email practices for more than a year, since reports surfaced that her unsecure clintonemail.com server sat in the basement of her Chappaqua, New York home while she served as the nation's top diplomat from 2009 to 2013.

'STONEWALL': Clinton senior aides including Huma Abedin – pictured on May 9 with husband Anthony Weiner, the disgraced former congressman – refused to meet with investigators probing the email scandal

Separately from the State Department audit, FBI agents have been probing whether Clinton's use of a private email server imperiled government secrets.

Clinton has acknowledged in the campaign that her homebrew email setup was a mistake, but said she never sent or received anything marked classified at the time.

Donald Trump attacked Clinton Tuesday night during a rally in Albuquerque, New Mexico, claiming her email scandal should have prevented her from running for the White House.

'She is as crooked as you get, believe me,' he said.

Clinton's campaign said Wednesday that 'while political opponents of Hillary Clinton are sure to misrepresent this report for their own partisan purposes, in reality, the Inspector General documents just how consistent her email practices were with those of other Secretaries and senior officials at the State Department who also used personal email.'

'The report shows that problems with the State Department's electronic recordkeeping systems were longstanding and that there was no precedent of someone in her position having a State Department email account until after the arrival of her successor.

'Contrary to the false theories advanced for some time now, the report notes that her use of personal email was known to officials within the Department during her tenure, and that there is no evidence of any successful breach of the Secretary's server. We agree that steps ought to be taken to ensure the government can better maintain official records, and if she were still at the State Department,'

On Twitter, Clinton's National Press Secretary Brian Fallon said, 'GOP will attack HRC because she is running for President, but IG report makes clear her personal email use was not unique at State Dept'

Fallon also pushed back at a CNN reporter who pointed out that Colin Powell, George W. Bush's Secretary of State, used a personal email address to conduct government business but did not route it through a private server.

'Only possible difference with server is in terms of security, not recordkeeping, & report says no evidence of successful hack,' Fallon stated.

Rep. Jason Chaffetz, a Utah Republican who chairs the House Oversight and Government Reform Committee, said in a statement that '[l]ong-standing weaknesses with the preservation of federal email records clearly exist within the Office of the Secretary of State.'