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The final attempt at the inaugural crewed launch of Boeing’s Starliner spacecraft is on track for Wednesday after a computer glitch halted the countdown just moments before liftoff on Saturday.

The historic mission, called Crew Flight Test, is scheduled to launch at 10:52 a.m. ET from the Cape Canaveral Space Force Station in Florida. The event will be streamed live on NASA’s website, with coverage beginning at 6:45 a.m. ET.

Veteran NASA astronauts Butch Wilmore and Sonny Williams will be the first crew to ride aboard the Starliner, powered into orbit on an Atlas V rocket created by United Launch Alliance, a joint venture between Boeing and Lockheed Martin.

The long-awaited flight was 3 minutes and 50 seconds away from liftoff Saturday afternoon when an automatic hold was triggered by the launch sequencer on the ground or by the rocket’s launch computer. The crews safely removed the astronauts from the capsule, and Williams and Wilmore returned to the crew quarters while fuel was drained from the rocket.

United Launch Alliance technicians and engineers assessed the ground support equipment over the weekend, examining three large computers located in a shelter at the base of the launch pad. Each computer is identical, providing triple redundancy to ensure the safe launch of manned missions.

“Imagine a big cabinet that’s a big computer, where the functions of the computer like the controller are separated separately on individual cards or printed circuit boards,” Tory Bruno, president and CEO of United Launch Alliance, said during a Saturday press conference. “They’re all standalone, but together, it’s an integrated controller.”

The cards in the computers are responsible for various key systems that must occur before launch, such as releasing bolts at the base of the rocket so it can rise after ignition.

During the last four minutes before the start, all three computers must communicate and agree with each other. But during Saturday’s countdown, a card on one of the computers responded six seconds slower than the other two computers, indicating something was wrong and triggering an automatic hold, according to Bruno.

Over the weekend, engineers evaluated the computers, their power supplies, and the network communications between the computers. The team isolated the problem to a ground power supply in one of the computers that provides power to the computer cards responsible for key countdown events — including the rocket’s upper stage replenishment valves, according to an update shared by NASA.

Starliner crews reported no signs of physical damage to the computer, which they removed and replaced with a spare. Meanwhile, mission specialists continue to analyze the faulty power pack to better understand what went wrong.

The other computers and their cards were also evaluated and all are working as expected, according to the ULA team.

Starliner’s mission management team reviewed the steps taken to troubleshoot the computer replacement and agreed that Starliner will launch on Wednesday, according to an update from NASA.

“I really appreciate all the work by the NASA, Boeing and ULA teams over the past week,” said Steve Stich, manager of NASA’s Commercial Crew Program, in a statement. “Specifically, the ULA team is working very hard to quickly learn more about these issues, inform our NASA and Boeing teams, and advocate for this next attempt.” We will continue to take it one step at a time.”

Mission teams successfully addressed several other issues that arose earlier in the countdown to Saturday’s launch attempt. These problems include the loss of data from ground valves responsible for replenishing liquid oxygen and hydrogen to the second or upper stage of the Atlas V rocket before liftoff.

Both the liquid oxygen and hydrogen used to fuel the rocket spring up while the rocket sits on the pad before launch, so replenishment continues until liftoff. After assessing the problem, the mission teams switched to a backup system for the valve data and were able to resume the process.

Weather conditions are 90 percent favorable for a launch Wednesday morning, with the only concern being cumulus clouds, according to the U.S. Space Force’s 45th Weather Squadron. If the launch doesn’t happen Wednesday, there is another opportunity at 10:29 a.m. ET Thursday, according to NASA.

If Starliner launches successfully, astronauts will spend just over 24 hours traveling to the International Space Station.

After docking, Williams and Wilmore will spend eight days in the orbiting laboratory, joining the seven astronauts and cosmonauts already aboard. The two will continue to test the functionality of the Starliner spacecraft while it is docked at the space station and then return home aboard the same pod. It is expected to parachute to land at one of several designated locations in the southwestern United States.

Meanwhile, the two astronauts remain in quarantine to protect their health before launch and practice procedures and simulations ahead of the historic flight, according to NASA.