Skype continues to slowly recover after an outage caused by problems with its peer-to-peer interconnection system.
The latest estimates say that 10 million users are now online, according to a blog post. Skype's outage began on Wednesday.
However, users able to get online can still expect that some features may not work as reliably as expected. For example, peoples' online status may be slow to update, and instant messages might not be delivered as quickly as they are normally, the blog post said.
However, it's not possible for Skype to predict when all users will be able to sign in and start making calls again, the company said.Around midday European time Thursday, almost 5 million users were back online, Skype said, which is around 30 percent of the number it would expect to see at that time of the day.
Skype at one point also disabled new downloads of its software, according to a Twitter message from a company spokesman.
Skype's initial description of the problem said many of the "supernodes" that act as directories for Skype users to find one another were taken offline by a problem affecting some versions of the Skype client.
"Our engineers are creating new 'mega-supernodes' as fast as they can, which should gradually return things to normal," the company blog post said.
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