This short article provides instructions on how to recover the full capacity of a USB flash drive following use with the Win32 Disk Imager software.
Fix instructions
Win32 Disk Imager is a great tool for taking an ISO disc image and writing it to a USB flash drive so that you can install an Operating System such as Linux on another PC without needing an optical drive or to waste a DVDR disc. However, one disadvantge with using this tool is that it tends to mess up the USB flash drive. If you try to reformat it using Windows or Linux chances are it will only format a portion of the drive leaving you with a much smaller capacity than you started with.
The following instructions will show you how to resolve this problem, restoring your USB Flash Drive to its former capacity.
Run CMD in Windows as an Administrator
Type: diskpart
Type: list disk
Note the number assigned to your disk and replace X in the next command with that number
Type: select disk X
Type: clean
Type: create partition primary
Type: active
Type: format fs=fat32 label="PENDRIVE"
The above command may take some time depending on the capacity of your drive
Type: assign
Type: exit
Safely eject the USB flash drive
Test it and check Properties to confirm original capacity now restored
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