State Department officials can't find the emails of Bryan Pagliano, the aide who set up Hillary Clinton's private server.

The agency is unable to search Pagliano's work computer for the emails, which were requested by the Senate Judiciary Committee, because the FBI has taken the computer into custody, according to a letter made public by Sen. Chuck Grassley's office Friday.

"The Department has searched for Mr. Pagliano's email .pst file, and we have not yet located one that covers the time period of Secretary Clinton's tenure," Alec Gerlach, a State Department spokesman, told the Washington Examiner Monday. "We are continuing to search for Mr. Pagliano's emails which the Department may have otherwise retained."

A .pst file stores emails and other items in Microsoft programs like Outlook.

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