WATERLOO, Iowa (AP) -- A woman is suing a Waterloo casino after she was denied a $42 million jackpot on a penny slot machine.

The Waterloo-Cedar Falls Courier reports Pauline McKee was playing the machine at the Isle Casino Hotel in July when the screen showed she'd won $42 million. The machine advertised a top payout of $10,000.

The casino didn't pay after a state investigator ruled the jackpot was caused by a computer malfunction.

McKee claims breach of contract and consumer fraud in a lawsuit in Black Hawk County District Court.

The casino hasn't filed a response, but is standing by an Iowa Racing and Gaming Commission investigation that determined the jackpot wasn't valid. McKee's attorneys argue, among other issues, the casino knew programming updates were available and didn't act on them.