After you have copied USB drive to image file, you can restore it later when needed. To do so, please follow the steps,
Run UsbToolbox, and click the button "Browse / Extract disc image file".

UsbToolbox shows the page for extracting disc image file.
Click "Browse" button to specify the source image file path and name. UsbToolbox will list files and folders in the selected image file.
Enter the extraction destination folder. The folder will be created automatically if it doesn't exist.

Click "More options" button to change other extraction options if needed.

Click "Start" button to start extracting image file to specified folder.
UsbToolbox will show the detailed progress message during the process. You can abort the operation by hitting Exit button at anytime.

You should get the message "Extracting image file completed successfully." on complete if no error occurs.
