From the Washington Post:
WASHINGTON — When Special Counsel Patrick Fitzgerald wanted to find out what was going on inside Vice President Dick Cheney’s office, the prosecutor in the CIA leak probe made a logical move. He dropped a grand jury subpoena on the White House for all the relevant e-mail.
One problem: Even though White House computer technicians hunted high and low, an entire week’s worth of e-mail from Cheney’s office was missing. The week was Sept. 30, 2003, to Oct. 6, 2003, the opening days of the Justice Department’s probe into whether anyone at the White House leaked the identity of CIA operative Valerie Plame.