UPDATE: KDDI said on Tuesday that it had finally succeeded in fully restoring its service after 86 hours of disruption.
Tens of millions of cell phone users in Japan were unable to connect for most of the weekend in what’s believed to be the country’s worst-ever service outage in terms of the number of lines affected.
Mobile carrier company KDDI said the disruption began early on Saturday and continued through Sunday, though some users were still experiencing problems on Monday.
The unprecedented outage impacted nearly 40 million customers, equal to about a third of the country’s population, national broadcaster NHK reported.
Affected services included KDDI’s “au” brand, as well as customers of UQmobile and Povo services, which use KDDI’s infrastructure.
It’s not entirely clear what caused the outage, though KDDI said it began when engineers were installing new equipment.
Users, some of them corporate customers, were unable to make calls or use the internet, leaving those desperate to make a call having to borrow a friend’s phone or seek out one of the decreasing number of public pay phones.
Unable to make calls, do online banking, organize deliveries, book rides, and take advantage of the myriad of other services normally available to phone users, tens of millions of regular customers were left extremely frustrated.
Communications minister Kaneko Yasushi said the incident was a concern because it also made it hard for some services to respond to emergency calls.
Responding to the debacle on Sunday while delivering the customary apologetic bow, KDDI president Takahashi Makoto said that he recognized the outage as a ”serious incident” and promised his company would respond appropriately according to Japanese law.
