N/APosted on - 11/02/2011
Yesterday, I installed and configured Microsoft Outlook 2010 and installed Hotmail connector plug-in order to use my two Hotmail accounts. At first, it all went good. Today, however, when I tried to sync process the send/receive, it gave me some error but only on my first account. The error number is: 0x8004102A
Problem encountered on hotmail accounts after Microsoft Outlook 2010 installation and configuration
This problems occurs when you delete a folder in the Microsoft Outlook and then delete the same folder in your hotmail server in a short time; before Outlook has time to synchronize the deletion. This searches for the folder in the mail server which is not there so causes a error message to be displayed. Usually this will be resolved after some time.
Another cause is when you deleted a folder in Outlook and then re add the folder in hotmail without syncing. If this happens error message will be displayed for a long time.
get the complete solution here at https://support.microsoft.com/en-us/help/2231628/outlook-hotmail-connector-users-see-error-0x8004102a-error-with-send-r