The social networking site has addressed complaints it was responsible for deleting users email information from their mobile phone contacts lists and replacing them with their own @facebook.com addresses.
Facebook has promised to solve the issue after blaming it on a software bug.
It follows news from last week when PCR reported that Facebook made it's own email addresses visible by default on its users profile, whilst hiding the ones originally listed.
The company has yet to confirm the scale of the bug or the number of users affected but it has been reported by The Verge and CNN Money that users running Facebook Contact Sync on Blackberry and Android phones, or devices running the beta versions of Apple iOS6 and Windows Phone 8 had been affected.
Facebook has attributed the bug to the application programming interface, which was designed to copy across its users primary email addresses - the ones used to log into the site.
However, a statement from the company admitted that: "for people on certain devices, a bug meant that the device was pulling the last email address added to the account rather than the primary address, resulting in @facebook.com addresses being pulled".
After deliberately changing its users contact listings last week, this latest error is only likely to further aggravate users and fuel their backlash against the site.
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