Can't imagine that the Axim51 was "never intended" to do that. I was able to sync files using WMP10 using my Toshiba E335 (PPC 2002), granted it had quite a bit less space on it.
I have successfully synched music, flawlessly, using Windows Mobile 5 on the Axim 51v but I prefer to just create my own folders and copy the music manually.
I'm sorry your having problems

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