Chaos at Greece's biggest airport El Venizelos, affected by massive blackout that has driven Microsoft's systems out of work.
According to one passenger of a flight to Germany, it reached the point of travel, but the plane never landed.
"We have been here since 8:00 a.m., we flew to Germany but they sent us back. Now we are here waiting and nobody tells us anything," he told Greek media.
Another traveller attributes the huge problem to delays to the fact that there was a global outage. "We hope the problem will be rectified soon. I hope my flight to Istanbul will take place immediately," he said.
Footage shows hundreds of citizens stranded at the airport, with children and elderly, due to the system's collapse that has affected Europe, Australia and the US.