Rich's Tongfamily (Richtong.net add-on)

Just when you thought iPods were easy, you get an unknown error (-39) to remind you that these really are computers and you can actually still see a return code. In my case, this is the error my iPod Photo throws because of a bad file somewhere.
You mainly have to be careful with iTunes that you don’t *change* this directory otherwise you lose *all* of your photos. Be caseful, just switching from say My Photos to c:\pictures will wipe *everything* out!
I haven’t seen this documented yet, but I have 3,000 photos and 5,000 tracks (I know I’m a nerd!) to get onto an iPod Photo. That causes its own instability. In my case, I have found that:
* TIF files. The really massive TIF files don’t compress correctly. If you have a 200MB TIF, you get garbage in the thumbnails. Plus it takes iTunes an incredibly long time to read and compress. (BTW, I have these from full resolution 35mm scans).
* JPG files. I have one or two files that seem to cause major headaches for iTunes. Again, there aren’t any error diagnostics except that iTunes would crash and leave me with nothing. I did find out that iTunes leaves a special directory called _iPod Photo Cache_ in the root of the directory being synchronized. This can get corrupted if it doesn’t translate the JPG correctly. You then get the (-39) error. The fix is to delete the iPod Photo Cache directory and it trys to translate again. By carefully copying certain files, you can figure out what the offending photo is.
Longer term, you really do have to undertand iPod internals I’ve found when these crashes happen. There are two things to understand for photos:
* iPodlounge Forums – Photo Storage on the iPod photo — The Gory Details. This is a great explanation of the files on the iPod. The iPod acts just like a standard hard drive, there is a directory called \Photos that has a whole series of chronologically sorted directories.
* On the PC there is this big iPod Photo Cache directory as I mentioned above.