I have been struggling with the error "Failed to connect to System Event Notification Service" for quite a while now on my development build of Windows 10 (1511). This error would pop up in the system tray for the first login if performed by an administrator.
The eventual fix was to use DISM and browse to my offline WIM and remove the entire C:\windows\logs folder , save your wim and reimage a machine. Hope this helps someone facing the same issue.
(Windows 7 Graphic - Same Error)