Astronaut Jeffrey Williams says "that's space business" after he is told to abandon his task after two hours.
NASA has halted an attempt to inflate an experimental room at the International Space Station (ISS) after hitting a snag.
Mission Control told astronaut Jeffrey Williams to abandon his task after two hours and put it on hold for at least a day.
It was supposed to take about an hour for the test chamber - the first inflatable room for astronauts - to increase four times in volume.
Scientists hope it could eventually prove to be a cheaper way of building a base on the Moon or on Mars, provided it is durable and does not let in too much radiation.
Mission Control radioed Williams, saying: "Thanks for all your patience today, and we'll hope for better luck tomorrow."
He replied: "That's space business."
The test had started off smoothly, as the astronaut opened a valve to allow air to slowly flow into the Bigelow Expandable Activity Module (BEAM).
He closed it as ground controllers monitored the increasing pressure inside the chamber.
He tried four more times before Mission Control told him to stop because of concerns over the pressure readings.
After a lengthy delay he tried again, but was told to pause. After that, NASA called the whole thing off.
NASA paid the module's developer $17.8m to test the inflatable-habitat concept at the space station.
It measures 2.1 metres by 2.4 metres and when fully expanded should measure 3.9 by 3.2 metres.
One benefit of inflatable spacecraft is that they can be packed tightly for launch, then expanded at their destination.