Can you change interfaces from usb to firewire?

[wildwell]

I can't get my external hard drive (that had been connected by firewire) to work when connected by USB. The light on the unit comes on but it fails to mount on my desktop.

It works great when I go back to firewire, but I want to free up a firewire port on the computer for something else. I know the USB port may be bad on the hard drive but I wonder if there's something else going on. It had always been connected via firewire in the past and was formatted over firewire. Is it possible the hard drive will only work over firewire now or am I just trying to ignore a defective USB port?

 

[r_manic]

Clarification: how are you connecting the firewire drive to your PC via USB?

 

[wildwell]

The drive has FW800, FW400, and USB 2.0.

 

[Mekugi Ana]

If the drive works over firewire, there's no reason it shouldn't work over USB. There are three possibilities on why it's not working. either the usb cable is bad, the usb port on the drive is bad, or the usb port on the computer is bad. There is one outlying possibility, that being that the computer isn't recognizing the drive over USB because it remembers it over firewire, but a reboot would wipe that out. One thing you could test is to plug it in and look in the system profiler under the USB section. If the drive is connecting properly, it should show up there. If it is there, you might try disk utility to see if it's also there. I forget, but you may be able to force the drive to mount from there it's listed.