USB Drive will not format with Disk utility

Edgar johnson

Registered
I got a USB drive for christmas and can't seem to do anything with it on my macbook.

When it's plugged in, i get a message saying "Error: Disk unreadable". Upon opening disk utility, it can't be seen, but nothing can be done to it for whatever reason.

I'm looking to get the drive operational but can't seem to find any way around this issue.

Any help on the matter would be greatly appreciated.
 
1. Is the external USB drive bus-powered, or mains-powered?
2. What Mac are you using?
3. In System Profiler > USB, is anything showing there?
 
Just spotted there's a typo in my first post... it can be seen in disk utility, just nothing can be done with it.

Bus-powered.
Using a two year old macbook [2Ghz Intel, 1gb ram]

The following shows in system profiler:

USB_DISK:

Capacity: 3.8 GB
Removable Media: Yes
Detachable Drive: Yes
BSD Name: disk1
Version: 10.00
Bus Power (mA): 500
Speed: Up to 480 Mb/sec
Manufacturer:
Mac OS 9 Drivers: No
Partition Map Type: Unknown
Product ID: 0x0201
Serial Number: 17409488245
S.M.A.R.T. status: Not Supported
Vendor ID: 0x1aa6

I have also tried to connect it to one of the windows computers in the house, and it's showing up without problem. Whether or not anything transfers I don't know, since I didn't want to risk causing any further problems.
 
Have you tried formatting it as Mac OS Extended (Journaled)? If it’s generic and formatted out of the box it's probably formatted for Windows.

You’ll find the formatting options under “Erase” in Disk Utility.
 
Instead of simply reformatting the partition, try creating a new partition map completely on the USB drive. In Disk Utility, click on the device itself (not the indented partition below the device listing), and click the "Partition" tab. Then, create a partition and set it to "Mac OS X Extended (Journaled)".
 
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