Where is the forum for Windows Live Mail please?
I have been instructed by a Microsoft Community Forum Moderator to seek help on the technet forum for this issue
https://answers.microsoft.com/en-us/windowslive/forum/livemail-email/windows-live-mail-is-creating-duplicate-sent-items/c67f67ed-285e-4dc0-9b77-2b363bb8240b?tm=1475834087116
thanks ...