Recover Lost Space on a USB Flash Drive

You may find the storage space on your USB has gone missing after using tools to Burn an ISO to USB. In which case, you will likely want to recover the lost or missing space on your flash drive. Further restoring the USB back to its full capacity. For example, when using tools like Etcher to DD (RawWrite) an ISO image to your USB device, its capacity becomes reduced to the size of the ISO file.

Obviously this can pose a problem if the original capacity of your flash drive is much larger than the image used. When raw writing an ISO to USB, the device assumes the filesystem of the Image, and any remaining space on the device becomes unallocated. As a result, devices left in this state can no longer be used for traditional storage purposes. To fix this you simply need to allocate the unused space to a new volume and partition. This new partition can then be used as a separate container for storage purposes.

How to Recover Missing Space on a USB Flash Drive

The following assumes the user is running from a Windows operating environment. I’ll follow-up with the procedure for Linux users as well.

  1. From the Windows Search box, type diskmgmt.msc and then press Enter.


  2. Next, (1) Locate your USB Disk from the list, (2) Right Click on the Unallocated Space and then select New Simple Volume.
    Create New Simple Volume
  3. When prompted, click Next to start the New Simple Volume Wizard.
    Create Simple Volume
  4. Now you can Specify Volume Size. Click Next to use all of the remaining space.
    Specify Size of New Volume
  5. Then you’ll be asked to assign a Drive Letter. Click Next.
    Assign Drive Letter
  6. Finally, to Format and Create the Partition. (1) Select a Filesystem. (2) Create a Volume Label. (3) Click Next.
    Format and Create Partition
  7. Click Finish to complete the creation of the New Partition.

If all went well you should now have access to the lost space on your USB flash drive.