Skype users were relieved after receiving strange error messages from Microsoft security products over the past week, after Microsoft admitted that it was a mistake.

Microsoft released a statement on Wednesday admitting that different antivirus definition update, released on Friday, had mislabeled Skype as a pop-up adware program called Win32/Vundo.gen!D, adding that the issue was fixed on Monday in a signature update.

Microsoft's security products were blocking Skype from running, but the firm said that users will not have to install new software once they update their antivirus definitions.

"Once the signatures are updated on the user's machine, Skype will operate normally," said Microsoft's public relations agency in a statement.