On the 18th in the morning, an access disruption in which videos did not appear on major screens such as the home screen on YouTube's mobile and web lasted about an hour before returning to normal.
YouTube said, "Due to an issue with the recommendation system, videos were not displayed on all YouTube screens, including the homepage, the app, YouTube Music, and YouTube Kids," and noted, "The homepage has been restored and we are working for a complete fix."
According to the industry, Google Korea reported to the Ministry of Science and ICT that a disruption in displaying the YouTube homepage screen began around 10:03 a.m. that day, and the service returned to normal around 11:07 a.m. The disruption also affected some functions of YouTube Music, but it was reported that watching videos through search and existing watch history was possible.
YouTube said it believes there was a data indexing error on the homepage screen during a service update and that it is identifying the detailed cause.
The problematic data was blocked to restore the screen, and guidance on the service's normalization was provided via the official blog and social media. Reports also surged on the outage monitoring site Downdetector, with more than 300,000 cases reported in the United States alone.