Time Machine, right. Will it work on a non Apple external hard drive, specifically a NAS? I haven't got Time Capsule, nor can I afford one right now. Can't get it to work on my Buffalo NAS at all. It refuses to create the back up disk image. I am trying to back up from my old Macbook Pro.

- does it have to be completely empty, formatted, to work? I have the contents of my old PC hard drive on there, it's not taking up much of the NAS [and it's in another folder which is meant to act as a separate partitioned part of the drive] but is that the problem?
- or will it just not work on anything but a Time Capsule? It's meant to be compatible but right now it bloody isn't, and the folks on the Apple help forum are [predictably?] telling me I have to get Time Capsule. Which I can't smegging afford.