Skype users have complained that private instant messages have been re-sent to unintended recipients.
A number of users have posted in the Skype support forums that parts of messages had been copied to a third party, others complain that whole conversations were sent to the wrong contact.
Skype is informing its customers that this is a rare circumstance and it is hoping to fix the problem within the next few days.
The bug appeared after an update to Skype in June, the company is urging users to download the latest update as soon as it is released.
Some users have said that this kind of bug has convinced them to stop using the video-calling service altogether.
One forum poster said: "This is still going on, entire conversation i had in the morning was sent to a wrong contact. This is it, i'm out!"
Another Skype user commented: "Same thing happened to me, my private conversation was shared with a contact which was business based in another country. Very embarrassing! I think Skype is Sh?te! I'm currently looking for an alternative!"
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