My USB device is detected with a ! or ? in Device Manager

If the device is in "Other Devices" (look for "USB Mass Storage Device") then it is possible that additional drivers are required for it, that Windows lost track of the drivers, or the drive is malfunctioning.

To see Device Manager, right-click on (My) Computer/ This PC > Manage > choose Device Manager from the left column.

  1. ensure you have Service Pack 4 (Window 2000) or at least Service Pack 1 (Windows XP).
  2. try another USB cable and another USB port.
  3. try another computer. If it works on another computer, the drive is fine but the Windows drivers on your computer need to be reloaded.
  4. If the drive is not detected there in the same way, go back to the USB Mass Storage Device and double-click on it. Look under the General tab.

If Code 28 appears:

  1. First see the Microsoft support article related to this issue.
  2. In general, Code 28 can often be overcome by following these steps:
    1. right-click on the drive (probably USB Mass Storage Device) and choose Uninstall
    2. turn off the drive
    3. reboot the computer
    4. turn the drive back on and retry.
  3. If the problem still continues, then you will possibly need to reload your USB controller drivers, which means you would need to insert your Windows install CD and boot to it to launch the Windows Repair.
    Warning: (This can be dangerous to your data, so use discretion when doing this.)

If Code 10 appears:

  1. First see the Microsoft support article related to this issue.
  2. In general, Code 10 often means, unfortunately, that the drive has failed. If the drive shows the same problem on another computer, try connecting the drive via 1394 (Firewire) if possible. If that is not possible, please replace the drive.

Related problems:

  • Windows Vista asks for drivers when I connect my Seagate/Maxtor external drive. See Document ID: 201235.
  • My locked Maxtor OneTouch drive does not show up anywhere. You must unlock your drive on this computer before it will be detected.
    -To unlock a Maxtor OneTouch 4 drive, see Document ID: 200271.
    -To unlock a Maxtor OneTouch III drive, see Document ID: 199871.

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