Skype has rolled out a new version of its Windows client to fix the technical issues that led to login problems and downtime on Thursday.
Late on Thursday, Skype blogger Peter Parkes wrote that the problems had been caused by "corruption... in a small percentage of users' systems that resulted in some of our community not being able to sign in to Skype".
"We issued some instructions which would allow you to get back online, but understand that they're fairly technical," Parkes wrote, adding that the company had subsequently pushed out a new version of Skype for Windows that automatically fixed the problem.
Parkes said a new version of Skype for Mac would follow on Friday, while Linux users should follow instructions for a manual update.
"If you're using Skype on your mobile, TV or other device, you should not have been affected by this problem, and should continue to be able to sign in as normal," Parkes added. "We're sorry for any disruption to your calls and chats today."