Certain Pictures cause errors???

[xenosaga01]

I have a 30gb Zen Vision W. My Computer is running Windows Vista Home Premium 64bit. I have a bunch of pictures of models that I downloaded from the internet. I am an artist and want to sketch them. For some reason, some of the pictures will transfer onto the player and some of them will not. Unfortunately my Zen library crashed, and I have to wait 2 hours to have my library rebuild, otherwise I would post the original error message it gives. The message says something along these lines: Your device has stopped responded or been disconnected....

Any help would be greatly appreciated.