I was genuinely impressed with the level of expertise that I have found here reading the answers to all the various issues with aperture. Thus my appeal for help. I can drag some photos directly from aperture onto my desktop or Iweb, but not others. In these cases the original photos are from the same camera. I cannot see any differences between the pictures, yet one will allow itself to be moved and the other not. Export will work, but this creates many extra steps in my workflow. Thanks in advance for any insight into this mystery.