Skype said its Internet phone service has returned to normal after a software bug left many users unable to log on for two days.
The company, a division of online auction company eBay Inc., said it would explain what caused the problem in more detail Monday.
"Until then, wed like to apologize and thank you. Precisely in that order," the company told its customers in a posting on its Heartbeat blog Saturday. "We know how difficult and frustrating the past two days have been. And still, your good wishes kept flowing in."
An estimated 220 million people worldwide use the Skype service, which lets its users make long-distance phone calls over the Internet.
The worldwide outage began Thursday. Users from Vietnam to Brazil to Germany to the United States said they could not log on and make phone calls or send instant messages. Skype said the issue was a problem with its software.
Skype, founded by Niklas Zennstrom and Janus Friis, uses peer-to-peer technology to connect phone calls, instant messages and videos between its users. It runs on a variety of operating systems, including Windows, Mac OS X, PocketPC and Linux.
Besides making computer-to-computer calls, Skype also connects cell phones and traditional landline telephones.