Skype blames buggy Windows software, swamped servers for outage

The bug in version 5.0.0152 of SKYPE caused old Windows clients to crash when they received a delayed response from "a cluster of support servers responsible for offline instant messaging" that had been overloaded, Rabbe said. About 50% of all Skype users were running the buggy 5.0.0152 version of the Windows client last week.