On Monday, many Skype users were unable to sign into the messaging service for several hours on their desktop and mobile clients. Microsoft finally fixed the issue and now they claim that a configuration change that it released that was bigger than usual was the root cause of the problems.
"We released a larger-than-usual configuration change, which some versions of Skype were unable to process correctly therefore disconnecting users from the network. When these users tried to reconnect, heavy traffic was created and some of you were unable to use Skype's free services, including messaging, presence, and contact list management. Others could not sign in or out of Skype altogether, or make calls to landlines or mobile phones. Skype for Business was not impacted."
Microsoft said it worked hard to re-balance the huge traffic load and that the problems were solved by around midnight GMT on Monday (that's 8 p.m. Eastern time). It added:
"No matter how quickly we were able to resolve this issue, it would not have been quick enough. We know many of you needed to use Skype during the outage, and finding that you couldn't would have been incredibly frustrating. We are extremely sorry for any inconvenience caused to our users, and appreciate your patience while we addressed the issue."
Microsoft's statement did not address what the company was doing to make sure the same problem would not happen again to its Skype services.