Connecting external HDD

Hi, I only recently got my 360, and I also got a 500GB Western Digital
USB/Firewire 'My Book' which I hear is supposed to work with the Xbox 360...

Problem is I can't seem to get the Xbox to see it.

I simply connect the USB lead at both ends, turn the HDD on, then turn the
Xbox on.. but it never seems to be detected.

I then realised the problem might be that the file system is NTFS, so I
reformatted the drive using FAT32 hoping that would do the trick, and I've
just tried it - but the problem remains!

Anyone know how I get this to work?



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