Jan Koum Apologizes for WhatsApp Going Down, Blames Faulty Router

February 23, 2014 Updated: July 18, 2015

Jan Koum, founder and CEO of WhatsApp, has apologized for the messaging service going down for four hours on Saturday.

Koum told the Verge that the outage was the longest and biggest in years and affected all of the service’s users.

The technical problem happened because of a faulty network router, which set of a cascading failure that ended up impacting Watsapp servers. That means the downtime likely didn’t happen because of the publicity accompanying the service being sold to Facebook and the resulting new users.

The service is working with its service provider to make sure that it won’t happen again.

The downtime wasn’t all bad news. A competing messaging service, the Telegram app, saw more than 6,000 people sign up per minute after WhatsApp went down.

However, the service later went down itself because of the overwhelming demand.

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