Rufus lets you quickly and easily reformat an ESXi USB flash drive back to full capacity

Posted by Paul Braren on Sep 10 2013 in
  • ESXi
  • HowTo
  • Hyper-V
  • Storage
  • :

    The executable is digitally signed and the signature should state:
    "Akeo Consulting" (v1.3.0 or later)
    "Pete Batard - Open Source Developer" (v1.2.0 or earlier)

    Rufus: Reliable USB Formatting Utility (with Source), read the introductionFAQ, and support forum.

    If you're trying to re-purpose a flash drive that already had ESXi installed on it, you'll likely notice that even after attempts at reformatting it, it still has a tiny capacity.

    This article will demonstrate a fix, step-by-step, showing that you can recover that flash drive very quickly and easily, with no command line stuff required. See also Rufus takes under a minute to create a bootable USB flash drive for ESXi installation Sep 10 2013

    Over the years, having had to deal with this formatting issue in my home lab quite often, and I'm quite glad to finally have a quick and simple fix.

    The advantages to using Rufus:

    • free
    • simple GUI
    • can be run from an EXE that doesn't require any installation
    • doesn't require careful attention to command line partitioning commands that can be a bit dangerous
    • much faster than other methods, takes under a minute to follow my instructions below
    • seems to work, every time, back on Windows XP, right through Windows 8

    Here's the 4 minute video demonstrating the actual 3 second method of getting your flash drive back to full capacity, using Rufus.

    , then follow the step-by-step instructions below.

    When User Access Control comes up, click Yes
    When asked 'Do you want to allow the following program to make changes to this computer' click Yes
    'Do you want to allow Rufus to check for application updates' just click No
    Verify you have the proper 'Device' chosen CAREFULLY! Be sure that all settings match the screenshot, and press 'Start'
    Rufus gives you one last warning that all data on your chosen device WILL BE DESTROYED, click 'OK'
    Once it completes, you can click the 'Close' button to exit
    Run Windows Explorer, right-click on the USB flash drive, choose 'Format...' then click 'OK'
    Click 'Restore device defaults' and type a descriptive Volume label, make sure 'Quick Format' is on, then click 'Start'
    Remember to safely eject the USB device when you're done with it

    For reference, here's other ways to regain your ESXi USB flash drive's full capacity.

    HDDGuru HDD Wipe Tool

    Reformatting an ESXi USB Stick by Ryan Birk, which highlights the use of HDDGuru HDD Wipe Tool.

    Some drawbacks though, including:

    • requires a full installation
    • takes a long time to format (many minutes), with no quick option.

    HP USB Disk Storage Format Tool

    This oldie but goodie didn't require an installation to run, and had a quick format option that recovered the full size of the flash drive. It's getting hard to find a safe place to download anything these days, this EXE included, explained here:

    Windows DISKPART

    How To Reformat a Bootable ESXi USB Flash Drive by Brian Graf (VMware), Jun 03 2013

    Works quite well, for those comfortable at the command line. No 3rd party software needed at all!