I'm using Firewire 400, running 10.5.5
I was using this drive with no problems for weeks. Now, when I power it on, it disappears from the desktop, and I get this message:
"Device Removal
The device you removed was not properly put away. Data might have been lost or damaged. Before you unplug your device, you must first select its icon in the Finder and choose Eject from the File menu."
But I never removed it, and it no longer appears in the Finder, so I can't eject it. I was able to run Disk Utility on it, and that said it was okay.