A computer fault has forced United Airlines to ground its flights in the US for the second time in recent weeks.
The firm blamed a "network connectivity issue" for the latest fault.
The two-hour long issue caused delays to more than 90 of its aircrafts, according to the FlightAware website.
The airline had to enforce a shorter flight ban on 2 June after incorrect data appeared in its flight planning system.
Shares in the firm fell more than 1.5% in morning's trade.
United is not the only carrier to have suffered such an IT-related setback over the past few months.
In April, American Airlines had to ground dozens of its jets after a flight plan tablet app, used by its pilots and co-pilots, stopped working.