Hi Enrique. It looks like I'm having the same problem as the others above. Nothing special with what I'm doing. Here's my steps:

1. I open up both apps (iPhone and Windows)
2. I discover the iPhone (it connects fine - altho it does list the phone twice. Once from auto-discovery and once from a manual discovery I set-up initially. Selecting either works just fine).
3. Once selected (iPhone shows "Client Connected"), I select the "Camera Roll" albumn. (~1200 Photos come up. 100/page).
4. I then click on "Backup Albumns", reselect the "Camera Roll" and click "Start Backup".
5. Next thing I see is the "Error - Load Albumn Contents" window that was included in a post above.

Note: I had changed the Backup Setting (new path and show status), so I thought something there might be causing the problem...but resetting back to defaults caused the same error.

I'm using iPhone 4. iOS 6.1.3

Any update on this? I have the same exact error when trying to back up ~1200 photos from the Camera Roll on my iPhone. Wifi is good. Apps are updated. Individual transfers ok.