SoftBank Group Corp. suffered a major disruption to its telecommunication service Thursday that lasted for hours and may have affected millions of users across Japan, including preventing people from making emergency calls to report a fire or request an ambulance.
The problem came less than two weeks before the telecommunication giant's mobile unit, SoftBank Corp, is scheduled to be listed on the Tokyo Stock Exchange in what could be the biggest-ever initial public offering in Japan.
Users began experiencing problems with phone and data connections at 1:39 p.m., and the issues continued throughout the afternoon until gradually being resolved from around 6 p.m., according to SoftBank.
An issue was found at several of its switching facilities, the company said. The Ministry of Internal Affairs and Communications is also investigating the cause of the problem.
The disruption caused some delays in parcel delivery services as drivers were unable to receive information regarding pick-ups and drop-offs, and caused problems for users of smartphone applications that require an internet connection.
Concertgoers at a Nagoya show featuring Japanese rock band Glay were unable to access QR codes that they were told to show along with their tickets to staff when entering the venue, forcing organizers to forgo the codes.
Air travelers using electronic boarding passes stored on their smartphones experienced similar problems.
SoftBank, the country's third-largest carrier by user base, had more than 40 million contracts as of the end of September including those with its low-cost Y!mobile brand.
Users of third-party firms that utilize SoftBank's network, so-called mobile virtual network operators, were also affected. MVNOs that use the network include Line Mobile and Mineo.
SoftBank plans to raise up to 2.6 trillion yen ($23 billion) by listing the mobile unit on the Tokyo bourse, outstripping the 2.2 trillion yen raised by the government through the sale of Nippon Telegraph and Telephone Corp. shares in its 1987 listing.