cannot get my new photos to upload into photos on windows 10
It appears that Microsoft may have resolved this.
The "items since last import" option has just now worked for me when importing photos from my camera. It looks like the quality update KB456900 which I installed on 25 July has fixed the problem.
I suggest others try it again if they've had the same update installed.
I'll post an update if this does not work next time I try it.