NBC News correspondent Andrea Mitchell said the federal finding that Hillary Clinton violated record-keeping rules during her tenure as secretary of state is "devastating" to her campaign for president.

It "completely undercuts the argument she has been making for more than a year," Mitchell said Thursday on MSNBC. "I don't see how this is anything but devastating ..."

MSNBC also played a clip showing Clinton saying over and over again that her private email server was allowed by the State Department, something that was not backed up by the inspector general report.

The inspector general for the State Department said Wednesday that Clinton "did not comply with the department's policies" when she used a personal email server for her electronic communications and declined to turn over many of her messages when her tenure ended.

The Clinton campaign responded to the report saying that "there is no evidence of any successful breach of the secretary's server." But Mitchell said Clinton's team should be handling it differently.

"They should have just come out arguably and said this is a mess and we're going to try move on," said Mitchell. "Instead, they're fighting it and coming out with a completely non credible argument on her behalf."