"USB Device not recognised"

Hey Community. 

My partner and I recently purchased a USB 2.0 powered 1TB My Passport for home use.  It had been working fine until last weekend at which point it stopped working entirely.  My Windows 7 o/s PC gives me a USB “device not recognised” pop up when we attempt to connect it and no amount of clicking on the 'troubleshoot device" helps and it is not recognised at all on our Macbook Pro which runs Snow Leopard. 

The harddisk is kept flat on a shelf when not in use and has never been dropped or banged around in any way, it’s less that 6 months old.  Whilst the data stored is just genenal back up and not overly important, I would greatly appreciate any information about firstly why this problem has occured and secondly what my options are for retrieving the data and replacement of the defective piece of hardware. I am in Australia if that is of any relevance for repair/retrieval. 

Is there a potential issue with external hard disks that are accessed by both mac and pc’s?  I have other, older external hdd’s which have been used over multiple platforms for years and not given me any problems.

Thanks very much in advance, I’d love to hear what the community suggests.

I don’t have any numbers to cite but a lot of people here are using a drive on mutiple systems and seem to have more problems. I believe there is a minor difference in format between XP and Vista and later. I would suspect your present problem is corruption. You can try this http://community.wdc.com/t5/Other-Externals/Elements-quot-needs-formatting-quot-help/m-p/6749/highlight/true#M86  see post 6. I assume you are formatted NTFS.


1 Like

Thanks Joe_S.

Unfortunately your suggestion wasnt able to solve my problem; the hard disk simply does not show up in the list of accessible HDD’s in Testdisk, which I was running in administration mode as suggested by the Test Disk FAQ.  I have attempted your solution on both my PC and MacBook, which produced no appreciable difference in results.

I’m not sure if this information is pertinent but I am quite sure that previously when we would use the HDD the light on the side would flash on a regular basis, however it now flashes rapidly upon initially plugging it in and then remains solid since we’ve been unable to access it.

Any further help would be greatly appreciated.

You have either bad connection issue or failed Ex-HDD. For connection problems just visually check (under a magnifying glass) both USB micro connectors on the drive and on cable. If all okay, you need to get your drive replaced.

1 Like

First of all if that drive was formatted for mac and pc simotanuosly (FAT 32) and if it had smartware on it. You can exspect the partion on that drive to have been damaged. Give us a little details.

What was the file system on the passport? NTFS, Mac OS exsteneded Journaled, FAT32?

What is the model number?

Laptop or a desktop? If desktop where is the connection? front, back, hub?

What is the drive status? (such as light blinking any noises?)

1 Like

Thanks again for the advice.  It really sounds like the device is bust and is going to need replacing though.

Lawrence, in answer to your questions; firstly the drive was formatted for FAT32, I chose to do that so that it would be accessible by both the PC and the Mac without the need for additional programs like Macdrive/NTFS for mac.

Secondly the model number is “WDBABM0010BB” or “WD PASSPORT ESSENTIAL USB2.0, 1TB, BLACK, External”.  

Thirdly, as I stated in the original post the Hard disk is used on both a Windows PC and a Macbook Pro so both desktop and laptop, I generally connect it to the USB hub on the front of the PC, though I have tried and used it on the rear ports in the past aswell. 

Finally,  when the device is connected to the PC I recieve a “USB Device not recognized” message, the light are soild for a few second, blink a few times then remain solid.  You are able to hear and feel the HD spin up but the light remain solid.  There is no prompt at all when connected to the Macbook.

I feel like I have provided most of this information in my previous posts, apologies if I was unclear.

Try formatting for mac or pc not FAT 32  and then installing the SES device driver


1 Like

Thanks Lawrence, I’ll give it a go.

However I’m not sure how I should go about formatting the device, in device manager on my PC it comes up as “unrecognised device” and simply doesnt show up on the Macbook.  Right clicking on the “unrecognised device” does not give a 'format" option.


It appears you and I have the same problem - although I haven’t been swapping between Mac and PC.  On connection to my PC, I get the Windows ‘device not recognised’ and the trouble shooter tells me ‘no drivers installed for this device’ and the Ex HDD doesn’t show up in any explorer or device manager areas.

I also have the solid blue light you describe.

Did you ever resolve the issue or was it a case of get another Ex HDD?