A Windows update has been pinpointed as the main reason Skype was offline for 48 hours last week (14 August). In a posting on the company's heatbeat.skype.com website Skype said, "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."
The disruption coincided with Microsoft's release of its August 2007 security update. According to Skype, the update from Microsoft caused users of Skype to reboot their Windows PCs. "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," Skype said.
Skype said, "We can confirm categorically that no malicious activities were attributed or that our users' security was not, at any point, at risk."