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I have a Transcend JetFLash 2GB USB Drive.It was working fine and I had been using it occasionally.

All of sudden it stopped working in all versions of Windows .USB Device not Recognised

Unknown Device

The USB Drive is also not recognised by the BIOS.It does not show in the list of bootable devices.(It used show up in the list earlier)

However the USB Drive works fine in my Linux Mint 11 OS.

Running dmesg gives this

[  941.812192] usb 1-2: new high speed USB device using ehci_hcd and address 4
[  941.936178] usb 1-2: device descriptor read/64, error -71
[  942.164188] usb 1-2: device descriptor read/64, error -71
[  942.380189] usb 1-2: new high speed USB device using ehci_hcd and address 5
[  942.504138] usb 1-2: device descriptor read/64, error -71
[  942.732179] usb 1-2: device descriptor read/64, error -71
[  942.948154] usb 1-2: new high speed USB device using ehci_hcd and address 6
[  943.364134] usb 1-2: device not accepting address 6, error -71
[  943.476172] usb 1-2: new high speed USB device using ehci_hcd and address 7
[  943.892140] usb 1-2: device not accepting address 7, error -71
[  943.892191] hub 1-0:1.0: unable to enumerate USB device on port 2
[  944.296190] usb 2-2: new full speed USB device using uhci_hcd and address 3
[  944.438251] usb 2-2: not running at top speed; connect to a high speed hub
[  944.709928] usbcore: registered new interface driver uas
[  944.729999] Initializing USB Mass Storage driver...
[  944.730509] scsi6 : usb-storage 2-2:1.0
[  944.730908] usbcore: registered new interface driver usb-storage
[  944.730917] USB Mass Storage support registered.
[  945.736320] scsi 6:0:0:0: Direct-Access     JetFlash Transcend 2GB    8.07 PQ: 0 ANSI: 2
[  945.744547] sd 6:0:0:0: Attached scsi generic sg1 type 0
[  945.753316] sd 6:0:0:0: [sdb] 3944448 512-byte logical blocks: (2.01 GB/1.88 GiB)
[  945.758274] sd 6:0:0:0: [sdb] Write Protect is off
[  945.758288] sd 6:0:0:0: [sdb] Mode Sense: 03 00 00 00
[  945.765167] sd 6:0:0:0: [sdb] No Caching mode page present
[  945.765181] sd 6:0:0:0: [sdb] Assuming drive cache: write through
[  945.784309] sd 6:0:0:0: [sdb] No Caching mode page present
[  945.784323] sd 6:0:0:0: [sdb] Assuming drive cache: write through
[  946.239512]  sdb: sdb1
[  946.257279] sd 6:0:0:0: [sdb] No Caching mode page present
[  946.257292] sd 6:0:0:0: [sdb] Assuming drive cache: write through
[  946.257302] sd 6:0:0:0: [sdb] Attached SCSI removable disk

Looks like there is something wrong the USB Drive.It is not recognised in any computer running Windows.

Is there any way to fix this?

Any idea why this problem occurred ?

share|improve this question
    
What is the file format it's in? –  Joseph Mar 16 '12 at 3:26
    
Which file system is the drive formatted as? –  iglvzx Mar 16 '12 at 3:29
    
What does sudo fdisk -l /dev/sdb print? –  Oliver Salzburg Mar 16 '12 at 3:41
    
Or cat /proc/mounts –  technosaurus Mar 16 '12 at 4:50
1  
Bottom line: the device is probably faulty and should be replaced. –  Harry Johnston Mar 17 '12 at 23:20
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2 Answers

Here are some things you can try :

  • While connected to the computer, unplug the power and after a few seconds plug it in again.
  • Try using the USB device with another USB port; if it works fine in another port the original port may have malfunctioned.
  • Shutdown the computer and disconnect it from the power for a long time so that all charge has dissipated from the motherboard. In the case of a laptop, removing the battery does the same thing.
  • Try using the USB device with another computer; if it works in another computer you know the problem is with the original.
  • If both computers have the same operating system and it works in one and not the other the problem would more likely to be a hardware one.
  • If the computer’s operating systems are different and it works in one it may be a compatibility problem with one of them. It could still be a hardware problem though.
  • Uninstall all USB controllers in Device Manager and restart the system. This will allow Windows to reinstall all of the USB controllers.
  • Make sure that BIOS is up to date (dangerous!)
  • Make sure that the chipset driver is up to date (motherboard)
  • Restore the operating system to a point where everything was working okay.
  • Give up on this USB as a pure lose.
share|improve this answer
    
It does not work on any computer running windows.Also there is no problem with the computer or the power supply as other USB Flash Drives are working fine.Looks like there is a power supply issue inside the USB Flash drive.Any way to troubleshoot that? –  bbalegere Mar 19 '12 at 1:53
    
The price of a 2GB USB doesn't justify repair, not mentioning that there are no repairmen for these. Buying a new one is the only solution. –  harrymc Mar 19 '12 at 6:26
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It might not show up in the BIOS if the first sector was overwritten for some reason.

The line here in your Linux logs:

[  944.438251] usb 2-2: not running at top speed; connect to a high speed hub

is unusual if your computer is USB 2.0 compliant and the flash drive is also USB 2.0 compliant - I don't believe they've made USB 1.1 only machines since 1998 or so. Is this flash drive connected to a hub that might be malfunctioning (they can do that over time)? Is it connected to an extension cable? Devices might be unable to negotiate USB 2.0 speeds properly if a connecting cable or the connector is damaged or improper in some way. This can cause Windows to complain but not Linux - Windows has more issues with USB device speed and detection than Linux does.

Since it's a Transcend device you might try running the Transcend recovery utility on it after backing up your data. Despite what it says about being an "online" tool, it's an executable you can download and run.

I would also suppose that antivirus software, which you would likely be running on Windows but not Linux, could be a possible cause, although I don't think it would stop the drive from being recognized.

share|improve this answer
    
Transcend Recovery utility is of no use as it does not even detect the presence of the USB Flash Drive. –  bbalegere Mar 19 '12 at 1:51
    
It was finicky when I used on such a device. I had to make sure nothing else was connected and I think it worked on the 3rd try. –  ultrasawblade Mar 19 '12 at 3:57
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