I get the same error. I have tried transferring photos from my iPhone 4 (IOS 6.0.1) to my Macbook Air and my PC and keep getting a 22 byte zip file.

I was able to transfer photos on Friday on my PC and it asked what resolution I wanted to download the files as, and now I just get the choice of either PNG or XMP.

Please help. I need to transfer photos to get them printed.

Thanks!