Having resolved a computer issue that prevented the previous launch attempt, United Launch Alliance has rescheduled the launch of Boeing and NASA’s CST-100 Starliner spacecraft for June 5.

Late on June 2, NASA declared that mission management had approved the Crew Flight Test (CFT) mission to be launched on June 5 at 10:52 a.m. Eastern, the next available launch window. There is a backup window on June 6 at 10:29 a.m. Eastern time.

The previous attempt to launch the CFT on June 1 was aborted three minutes and fifty seconds before takeoff. According to ULA, one of the three redundant ground control computers’ launch sequencer cards came up more slowly than the other two when it came time to release a prearranged hold at T-4 minutes. ULA CEO Tory Bruno surmised that the event might have been caused by a hardware or networking issue.

NASA released a statement stating that ULA discovered an issue with a power supply unit that was utilized by some of the cards in one computer. This includes the card, which also failed earlier in the countdown, that regulates the valves on the Centaur upper stage that replenish propellant.

NASA noted that ULA made the decision to swap out the malfunctioning power unit for a spare computer rack, or chassis, while technicians looked into the reason of the power supply failure. According to NASA, “ULA has completed functional checkouts of the new chassis and the cards, and all hardware is operating normally.”

Once more, ideal weather is predicted for the launch on June 5, with a 90% chance of excellent conditions. NASA did not disclose any other problems being investigated pertaining to the Starliner spacecraft or the Atlas 5 rocket and its ground support apparatus.

NASA astronauts Butch Wilmore and Suni Williams will go on Starliner to the International Space Station as part of the CFT mission. They will stay there for approximately a week before landing back in the southwestern United States. Before NASA certifies the vehicle for use on operational trips to the International Space Station beginning as early as 2025, this mission serves as the last test flight.

NASA and ULA have stated that they will step aside to work on the rocket itself, including repairing the rocket’s aging batteries, if Starliner does not launch by June 6. They estimated that the task would take ten days to finish.