Hillary Clinton’s myriad statements explaining her exclusive use of personal email for official business while secretary of state are coming under heavy fire from all sides in the wake of a damaging inspector general report – and her campaign’s insistence the report proves her practices were nothing unusual is being met with similar criticism.

Top Republicans from presumptive presidential nominee Donald Trump to House Speaker Paul Ryan slammed Clinton over the report, accusing her of breaking agency rules to “serve her own interests” and putting security at “risk” in the process. But aside from shows of support from Democratic allies on Capitol Hill, other prominent voices in Washington were similarly unsparing toward the Democratic presidential front-runner.

The headline on The Washington Post’s editorial Thursday blared, “Clinton’s Inexcusable, Willful Disregard For The Rules.”

The board wrote that the State Department inspector general audit makes clear her email use “was not a casual oversight,” and Clinton “ignored” repeated warnings to use official communications.

In March 2015, Clinton described her email set-up as a “matter of convenience,” and insisted, “It was allowed.”

But the report, which was formally released Thursday, said investigators found no evidence Clinton “requested or obtained guidance or approval” to conduct official business on her personal email account or server despite having an “obligation” to discuss this. The report said had she notified the appropriate offices, they would not have approved her “exclusive reliance” on a personal account.

The audit said employees also were instructed to use “approved, secure methods” to send information known as “sensitive but unclassified” – yet emails on Clinton’s account “regularly contained information marked as SBU.”

After details of the report first circulated on Wednesday, Clinton campaign spokesman Brian Fallon issued a statement pointing to “longstanding” problems with department recordkeeping and describing Clinton’s practices as “consistent” with those of her predecessors. The statement echoed Clinton’s claims throughout the campaign, holding up the IG audit as proof.

"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,” he said. “… But as this report makes clear, Hillary Clinton's use of personal email was not unique, and she took steps that went much further than others to appropriately preserve and release her records."

Fallon later told Fox News that regulations did not bar using personal email for work purposes, again noting that other officials had done so going back years.

The report did say the department long has had issues with email records, and “email usage and preservation practices varied across the tenures of the five most recent Secretaries.”

But the report highlighted Clinton’s practices as out of the ordinary, especially for someone at her level – and coming into the job as new guidance was being issued. The IG found only three cases where officials used non-department accounts “on an exclusive basis for day-to-day operations.” Just two of those cases involved secretaries of state: Colin Powell and Clinton.

And the report noted that during Clinton’s tenure, the guidance was “considerably more detailed and more sophisticated” than in the past. Yet she still defied the guidelines.

Further, while Clinton has said she’s happy to talk to “anybody, anytime” about the issue, the report said she declined an OIG request for an interview, though her predecessors made themselves available. Aides Huma Abedin, Cheryl Mills and Jake Sullivan also declined interviews with government investigators.

Regulations show they were essentially required to help the inspector general, who has broad powers to compel testimony.

On another front, Mills also reportedly has asked a federal judge to intervene and prevent any recordings of her scheduled deposition to a conservative group about the email system from being released.

The IG report also showed department staffers shielding Clinton’s set-up from scrutiny.

The report said two staffers said they discussed their concerns in 2010 with officials, but were told Clinton’s personal system had been approved “and the matter was not to be discussed any further.” One staffer said a top official with Information Resource Management “instructed the staff never to speak of the Secretary’s personal email system again.”

Clinton, too, was personally involved in the decision-making. In November 2010, Clinton aide Abedin emailed Clinton about the possibility of getting her on an official email account. Clinton responded, “Let’s get separate address or device but I don't want any risk of the personal being accessible."

The report also raised questions about security risks, pointing to one message from an adviser that acknowledged her system was “attacked” in 2011, though it apparently failed.

But perhaps the most explicit violation pertained to recordkeeping rules.

The report said 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. At a minimum, Secretary Clinton should have surrendered all emails dealing with Department business before leaving government service.”

She did not, the report said, and therefore “did not comply with the Department’s policies that were implemented in accordance with the Federal Records Act.”

Republican National Committee Chairman Reince Priebus said “she was in clear violation of the Federal Records Act.”

In this case, the inspector general report faulted Powell for the same violation.

Fox News’ Catherine Herridge and FoxNews.com’s Judson Berger contributed to this report.