Skype said that it has stabilized its service following a two-day outage and gave details about reimbursing users. Pay As You Go and Pre-Pay users will receive a credit voucher via e-mail that will give them approximately 30 minutes of free calling anywhere in the world, the company said. Meanwhile, subscribers will get a credit within the next few days for an extra week of service.
The cause of Skype's massive outage on Wednesday that blocked millions of users from making Internet telephone calls is still unclear, according to Tony Bates, Skype's chief executive.
"We're still digging into what caused the initial trigger," said Mr. Bates in an interview Thursday afternoon. Whatever the trouble was, however, it prevented a large number of Windows users from making calls, raising ire across the globe and tarnishing Skype's image as an important telecommunications company of the digital age.
Skype's collapse started Wednesday morning. Although the company assured users it would restore service in a few hours, the problems continued through Thursday. "It took a little longer than the initial estimates from the team," Mr. Bates said. As of around 3 p.m. E.D.T. Thursday, Mr. Bates said that Skype had 17.6 million to 20 million users simultaneously online, or around 90 to 95 percent of normal. Some users may still be having difficulties making calls, he acknowledged, but said that, if so, it is because the company is trying to restore service in a controlled manner.
Skype's problems are with what are called "supernodes," computers among its network of 124 million users that serve as phone directories and help connect calls. For unknown reasons, they were taken offline, leaving the network in chaos. Mr. Bates declined to reveal how many supernodes exist. Skype's users are not told whether they host a supernode.
So given the troubles with supernodes, is Skype rethinking its reliance on them? Mr. Bates said they are fundamental to how Skype operates. In any case, Skype technicians are creating new nodes on internal servers by displacing server space normally dedicated to Skype's instant messaging and group video conferencing. As a result, those services may not be restored to normal for a few days.
Skype's business, which depends on users paying to make calls to landline or mobile phones, will be impacted because it calls into question its reliability. Mr. Bates, who joined the company last month, is trying to find other sources of revenue like corporate phone service and mobile phones. Corporate customers, even more than consumers, need a phone system that always works.
"It's hard to assess what if any impact there will be," he said. Later on Thursday, he said that Skype will announce details of a plan to compensate paying customers for the loss of service.
In August, Skype filed for an initial public offering, which is likely to take place next year. Bates declined to give any updates on the proposed offering. However, the outage should not have a material impact on the company's finances, Mr. Bates said.