NTT Docomo Area Mail fails to deliver 16 October quake alert
Docomo says an internal system fault, not a cyberattack, stopped its emergency alert reaching users across much of Japan; KDDI and SoftBank delivered normally.
NTT Docomo has reported that its Area Mail emergency alert service failed to deliver the Earthquake Early Warning issued by the Japan Meteorological Agency around 12:40 on 16 October 2026, according to k-tai.watch.impress.co.jp. The warning was later cancelled.
The alert was intended for all users in Hokkaido, Tohoku, Hokuriku, Kanto, Koshinetsu, Tokai and the Izu Islands.
Docomo attributed the failure to a fault in its own system and said it was not a cyberattack. The company said it has identified the cause and is working urgently to fix it.
Docomo also warned that Area Mail may not be delivered correctly until the fault is fully resolved.
KDDI and SoftBank delivered the same alert without problems.
Quick answers
Why did NTT Docomo's Area Mail not go out on 16 October 2026?
Docomo said the cause was a fault in its own system, not a cyberattack, and that it has identified the cause and is working to fix it.
Which areas were meant to receive the alert?
All Docomo users in Hokkaido, Tohoku, Hokuriku, Kanto, Koshinetsu, Tokai and the Izu Islands.
Did other carriers deliver the warning?
Yes, KDDI and SoftBank delivered the alert without problems.