President Fred Cummings said all stations east of Royal Oak on the Expo Line, and Braid and Sapperton on the Millennium Line were affected due to a failed card in the I/O rack of the main control computer that had to be replaced.
Customers weren't happy and took to Twitter to voice their concerns.
My poor mom had to take a taxi from Metrotown to Surrey because of the Skytrain problem," tweeted @zoeylynngauvin. She should receive a refund. Ridiculous!"
"I'm having a mental breakdown cause the Skytrain isn't working and I need to get from Langley to East Vancouver," tweeted @givemeasin
A bus bridge was put in place between Metrotown and King George to accommodate customers affected by the delay, and customers were also asked to consider using buses.
Limited service between Waterfront to Metrotown station on the Expo Line, and Lougheed to VCC-Clark Station on the Millennium Line.was restored shortly before 6 p.m. PT.
However, Cummings said an automated system-wide hold was initiated after some passengers on stopped trains exited their trains and entered the Skytrain guide way.
He says SkyTrain attendants manually drove trains back to their platforms to ensure passengers could leave the system safely.
By 6:45 p.m. PT, all passengers had been removed according to Cummings.
However, the computer problem wasn't fixed until 8:15 p.m. PT, when all trains began to resume service.
"We apologize to our customers for this unusual incident, which caused parts of our SkyTrain system to be out of service for such a lengthy period of time," said Cummings. "We operate a complex system with many moving parts, and we work hard to keep our system in good repair and keep it running smoothly for our customers."
Commuters reported problems at some stations following the 8:15 p.m. PT restoration of service, but most of the Skytrain line was up and running by 10 p.m. PT Thursday.