Skype Details the Great 2010 Outage

On Wednesday, December 22, a cluster of support servers responsible for offline instant messaging became overloaded. As a result of this overload, some Skype customers received delayed responses from the overloaded servers. In a version of the Skype for Windows client, the delayed responses from the overloaded servers were not properly processed, causing Windows customers running the affected version to crash.

The latest Skype for Windows

Users running either the latest Skype for Windows, older versions of Skype for Windows, Skype for Mac, Skype for iPhone, Skype on your TV, and Skype Connect or Skype Manager for enterprises were not affected by this initial problem. But, around 50% of all Skype users globally were running the 5.0.0.152 version of Skype for Windows, and the crashes caused in broad outline 40% of those customers to fail. These customers included 25–30% of the openly available supernodes, as well failed as a result of this problem.