You would have definitely seen the below error message if you have used USB devices and external hard drives in your Windows Machine.

Problem Ejecting USB Mass Storage Device  Error Message

Though the error message explicitly states that the USB is still in use, you won’t be able to find which program is using it and may drive you nuts.
Even after closing all the applications or programs that were using your USB, when you try to eject the USB device it will still throw you the same error message. So let us quickly see how to fix it.

  • Right click on My Computer and click Manage.
    Manage My Computer
  • In the Computer Management screen, select the Disk Management under Storage from the left panel.
  • Right click on the drive that you would like to remove safely and click Eject.

Eject USB Device

  • If the device that you are using is an external hard disk then you would see the option “Offline” instead of “Eject“, refer the below screenshot.

Offline Option for External Hard Disk

Note: When you have selected the option “Offline” in case of external hard disk, you still have to go to the task bar, right click and Eject your device. And when you insert the external hard disk back into the system you have to go to the Computer Management Screen and bring the device Online, else the device won’t be available for you to use.

External Hard Disk Online

Hope this quick fix gets you out of the “Problem Ejecting USB Mass Storage Device” error message.