NTT DoCoMo Inc. said Wednesday it had rectified a glitch affecting its international roaming services that may have inconvenienced tens of thousands of customers of its World Wing service.
The glitch, which affected users in as many as 220 countries and territories since Monday evening, was fixed and services resumed fully at 2:13 a.m. Wednesday, Japan's largest mobile communications service provider said.
On Tuesday, DoCoMo said that problems with voice calls, emails and Internet services seen since around 6:24 p.m. Monday were almost resolved as of 10:13 p.m. Tuesday, thanks to the use of the lines of at least one local telecom company in each country.
DoCoMo earlier said its international circuits may have been overburdened by increased traffic volumes and may have been affected by a rise in overseas travelers during the summer vacation season.
The carrier said it was anomalous for the key function of mobile phones — voice calls — to be disrupted for almost a day, and it was working flat-out to restore services and investigate the cause of the problem, while reporting to the Ministry of Internal Affairs and Communications.
The disruption in international roaming, which enables customers to use their Japanese mobile phones abroad, comes only days after similar problems at DoCoMo on Aug. 2 and 3. While those triggered disruptions to domestic services, the latest problem had not had any impact domestically, it said.