The State Department is lying when it says it didn’t know until it was too late that Hillary Clinton was improperly using personal e-mails and a private server to conduct official business — because it never set up an agency e-mail address for her in the first place, the department’s former top watchdog says.

“This was all planned in advance” to skirt rules governing federal records management, said Howard J. Krongard, who served as the agency’s inspector general from 2005 to 2008.

The Harvard-educated lawyer points out that, from Day One, Clinton was never assigned and never used a state.gov e-mail address like previous secretaries.

“That’s a change in the standard. It tells me that this was premeditated. And this eliminates claims by the State Department that they were unaware of her private e-mail server until later,” Krongard said in an exclusive interview. “How else was she supposed to do business without e-mail?”