 -- The Hillary Clinton email controversy has dogged the former secretary of state for more than a year and has now reached new prominence as the Democratic presidential contender attempts to fight off a challenge by Sen. Bernie Sanders.

Yesterday, a report released by the State Department’s Office of Inspector General said that Clinton shouldn't have used a private email server to conduct official business and would have not been allowed to do so had she asked. It also found that she violated department policy.

Clinton has not been charged with a crime and her spokesman, Brian Fallon, said the former secretary's email use was in line with former secretaries of state. He also said that political opponents were using the report in a misleading way.

Here are five important takeaways from the report:

This Report is About Rules, Not Laws

The report essentially says that Clinton (and a number of her predecessors) failed to comply with recommended email policy and established practices of record-keeping. In Clinton’s case, the report says she wouldn’t have been allowed to exclusively use a private email account during her tenure had she asked to do so -- which she did not. Furthermore she didn’t turn over all her email before leaving, which she was supposed to do. Questions about any potential crime are expected to be answered upon conclusion of an FBI investigation, which is completely separate. Instead of focusing on whether she should have been using private email, like this investigation did, the FBI is trying to find out if anyone is responsible for mishandling sensitive information.

Contradictory Statements?

If you visit Clinton’s campaign website, you will see talking points about her private email that say no rules were broken. “Was it allowed?” her website asks about her use of private email. “Yes. The laws, regulations, and State Department policy in place during her tenure permitted her to use a non-government email for work,” the answer reads. But yesterday’s report offered a more nuanced answer. It said that guidelines produced by the State Department during her tenure discouraged the use of private email and identified the risks of doing so, also saying that official State Department email should be used in “most circumstances.” Clinton never used it in any circumstance. The report also says that Clinton should have handed over her official emails after leaving. “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 report says.

Lack of Cooperation

Earlier this month Clinton, in response to questions about the FBI probe, Clinton said in an interview with CBS News that she would be willing to cooperate with any investigation. “I think last August I made it clear I'm more than ready to talk to anybody anytime,” Clinton said at the time. But according to this report, that’s not true. The Inspector General’s office says both Clinton and her aides declined to be interviewed for the report. The four other secretaries investigated in the report: Madeline Albright, Colin Powell, Condoleezza Rice and John Kerry, all participated in interviews.

Hacking Attempt

The report revealed that Clinton’s aides were very concerned about actual attempts to hack her email. In previously unseen emails between her email technician and one of her staffers, it’s revealed that they actually shut down her server at one point for fear that it was going to be breached by cyber intruders. On Jan. 9, 2011, the technician "notified the Secretary’s Deputy Chief of Staff for Operations that he had to shut down the server because he believed 'someone was trying to hack us and while they did not get in i didnt [sic] want to let them have the chance to.'" Later that day, the adviser again wrote to the Deputy Chief of Staff for Operations, “We were attacked again so I shut [the server] down for a few min,” the report said. The next day, the Deputy Chief of Staff for Operations emailed the Chief of Staff and the Deputy Chief of Staff for Planning and instructed them not to email the Secretary “anything sensitive” and stated that she could “explain more in person,” the report said. Clinton has maintained that her private email was never successfully hacked.

Clinton Emails We Haven’t Seen

Another major revelation from this report is that the State Department has an undisclosed number of emails in its possession that weren’t released to the public. It turns out roughly 52,000 pages the State Department put online only accounts for the email she could find and turned over. However, the Department has emails it found on its own, but did not release in that massive tranche, the report said. In one previously unseen email between Clinton and her deputy chief of staff, they discuss her use of private email. “In November 2010, Secretary Clinton and her Deputy Chief of Staff for Operations discussed the fact that Secretary Clinton’s emails to Department employees were not being received,” the report reads. “The Deputy Chief of Staff emailed the Secretary that “we should talk about putting you on state email or releasing your email address to the department so you are not going to spam.” In response, the Secretary wrote, “Let’s get separate address or device but I don’t want any risk of the personal being accessible.”

Asked today how many more unseen emails from Clinton the State Department has in its possession, State Department Spokesman Mark Toner said today that he wasn’t sure. He insisted it’s not a large number.