She said that shortly after the letter was sent, ES&S officials "came in and addressed each issue point by point. Each one has either been resolved or they will be required to find a solution."

She was unsure when ES&S will complete the compliance process.

An ES&S spokesman said the error was caused by a tester using her fingernail instead of her fingertip on the touch screen to cast a vote. The firm's iVotronic machines require that the fingertip be used, he said. The spokesman also noted that voters can review ballots before they are submitted.

The letter to ES&S also cited the tester's inability to see all of the choices on a single screen.

The spokesman said that the tester accessed the screen that summarized the number of votes cast and that the system does allow the viewing of all choices on a single screen.