News

Skype Outage Caused by Microsoft Update

A two-day outage that left millions of Skype users unable to use the popular Internet phone service was caused by an abnormally high number of restarts after people had downloaded a Windows security update, the company said Monday.

The worldwide outage, which began on Thursday and ended on Saturday, left millions of Skype users unable to log on to make phone calls or send instant messages.

Luxembourg-based Skype Ltd., part of online auction giant eBay Inc., has more than 220 million users in total but typically has 5 million to 6 million users online at any given time. In January, Skype reported that it had counted 9 million users online at one time.

In an update to users on Skype's Heartbeat blog, employee Villu Arak said the disruption was not because of hackers or any other malicious activity.

Instead, he said that the disruption "was triggered by a massive restart of our users' computers across the globe within a very short timeframe as they re-booted after receiving a routine set of patches through Windows Update," Arak wrote.

Microsoft Corp. released its monthly patches last Tuesday, and many computers are set to automatically download and install them. Installation requires a computer restart.

"The high number of restarts affected Skype's network resources. This caused a flood of log-in requests, which, combined with the lack of peer-to-peer network resources, prompted a chain reaction that had a critical impact," Arak wrote.

Arak did not blame Microsoft for the troubles and said the outage ultimately rested with Skype. Arak said Skype's network normally has an ability to heal itself in such cases, but a previously unknown glitch in Skype's software prevented that from occurring quickly enough.

Users from Vietnam to Brazil to Germany to the United States had complained they could not log on and make phone calls or send instant messages.

The outage was a critical moment for the company, founded in 2003 by Niklas Zennstrom and Janus Friis, and was the first major outage since October 2005 when its service was down only for a few hours.

"This disruption was unprecedented in terms of its impact and scope," Arak wrote. "We would like to point out that very few technologies or communications networks today are guaranteed to operate without interruptions."

Featured

  • Motherboard Image

    Darktrace Deal To Bring AI Security to Microsoft Products

    Microsoft and security solutions firm Darktrace plan to integrate the latter's AI products with Microsoft Azure, Azure Sentinel and Microsoft Defender for Endpoint.

  • 2021 Microsoft Conference Calendar: For Partners, IT Pros and Developers

    Here's your guide to all the IT training sessions, partner meet-ups and annual Microsoft conferences you won't want to miss.

  • Microsoft Updates Azure Icon, Plans Default Font Change

    Microsoft recently announced a few planned design changes, including a new Azure icon.

  • The 2021 Microsoft Product Roadmap

    From Windows 10X to the next generation of Microsoft's application server products, here are the product milestones coming down the pipeline in 2021.