The shuttle crew performed the inspection with a sensor-laden boom attached to the ship's robotic arm. Such checks have been standard since the 2003 Columbia disaster when debris from the fuel tank knocked a hole in the wing causing the craft to disintegrate, killing all astronauts on board.
Engineers thought they saw a 12-to-18-inch strip of insulation fly off the rear of Endeavour, but images relayed by the astronauts on Saturday appeared to show nothing amiss.
"There's no apparent damage there," lead flight director, Mike Sarafin, told reporters on Saturday night.
NASA is still assessing a flyaway object that was spotted on a video of the shuttle's takeoff.
"It looked like something was clearly there," Sarafin noted.
The issue is however, considered minor, as was a glitch with one of the shuttle's communications antennae.
The shuttle, which rocketed off from the Kennedy Space Center in Florida on Friday night, is on schedule to arrive at the International Space Station (ISS) on Sunday at 22:04 GMT where it is expected to remain for 11 or 12 days.
Astronaut Sandra Magnus will swap places with space station flight engineer, Greg Chamitoff, who has been aboard the ISS since June. Endeavour is carrying over 7 tons of equipment for the station, including two new sleeping compartments and a water recycling system that will allow crew members to purify urine and other wastewater for drinking. The renovation project will mean that six full time residents can live aboard the station, rather than the current limit of three.
The shuttle crew is also planning to carry out four spacewalks in order to repair the station's solar power system.
The International Space Station, a $100 billion project involving 16 member nations, orbits 220 miles above the earth and has been under construction for 10 years.