Boeing has run out of time to find out why.Extended TroubleshootingBoeing's CST-100 Starliner spacecraft, which the company has been working on for many years, should have been ready to launch from the International Space Station. Instead, it's stuck here on Earth.SpaceNews reports that the Starliner was scheduled to launch an uncrewed test flight on August 3rd. However, the mission was canceled three hours prior to launch. The propulsion system valves were stuck in closed position. Engineers are still trying to figure out the reasons, but they believe the spacecraft was damaged by a storm during transport.Boeing won't have much time to solve the problem before it is overshadowed by the busy schedule of the space stations in the next months.Be cautiously optimisticStarliner's history is long and has been plagued by software, hardware, and other delays. Last February, Boeing completely skipped a critical safety test. The company claims that it is optimistic about its future.AdvertisementAdvertisementIn a statement to SpaceNews, John Vollmer, Boeing vice president and program manager for commercial crew programs, stated that being cautiously optimistic is a good way of describing how the team feels.If Boeing hopes to fly the Starliner in 2018, it will need to be able to rely on its optimism. SpaceNews reports that if Boeing misses its window, NASA and SpaceX missions may force it to wait until November to launch the experimental spacecraft. SpaceX's crewed spaceflight program is the next priority for Boeing. The company must act quickly if it wants to catch up.READ MORE: Starliner investigation continues [SpaceNews]The Starliner: Boeing is still trying to get its doomed space shuttle off the groundAdvertisementAdvertisement