100Mb ? Wow, I've never heard of any mp3s THAT big!

Anyway, did you leave enough time for your iTunes to import the file? Maybe you too have to wait a bit.
Also, I'm an OSX user and relatively new (compared to others in here...) so I can't really tell you what to do, sorry

(I'll try and help as much as I can though)

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iMac G4 OSX 10.3.9
RAM 256MB
LW 4.10.5 Basic
ADSL anything from 3 to 8Mbps/around 1024kbps

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