Impossilbe to format EFI in FAT32 using DISKPART

  1. Posts : 5

    Impossilbe to format EFI in FAT32 using DISKPART

    Hi all,

    This is the first time for me to install W10 and I am facing a kind of strange issue.
    All started with an error code displayed by the W10 installer saying something like "Impossible to format system partition. Wrong file system. Error Code 0x80042425"...
    After so Google search most of the answers were linked to USB key issues as I am booting using a bootable USB Key...Change the key for a bigger one (8Go => 16 Go) no changes...

    Browsed a bit more on Google and understood that W10 is based on 4 partition :
    2. MSR
    3. Windows
    4. Recovery

    Made the link with the previous error understanding that it was not a key issue but a system partition formating issue.
    Started to look around and finally landed on that page from Microsoft (in french sorry):In between I got accounted to GPT/EFI rules and noticed that for W10 if EFI boot required, then GPT based disk is mandatory + for W10a dedicated EFI partition in FAT32...
    And this is where I am facing the issue with DISKPART.
    Getting thru the script provided on the MSDN site I have no issue until that line :
    format quick fs=fat32 Label="System"
    Diskpart retuns me the following error:
    virtual disk service error the file system is incompatible
    Formatting using exFAT or NTFS works but for sure will not solve my W10 installed problem...As additional information :

    • I am trying to install W10 on a CRUCIAL 525GO MX300 SSD
    • CSM is disabled
    • Fastboot is disabled
    • Secure boot is disabled

    Any help from a partition Guru would be highly appreciated :) !
    Thks a lot
      My Computer

  2. Posts : 17,369
    Windows 11 Pro

    If you are trying to do a clean install then select the custom install option. Delete each partition listed on the SSD until you have nothing but unallocated space. Highlight the unallocated space and click next to let it set up the partitions on the SSD.
      My Computer

  3. Posts : 5
    Thread Starter

    THks NavyLCDR ofr your prompt reply.

    Maybe it was not clear in my description but I already did that....And it doesn't work....Installation won't start (step 02) and I get the following message from Windows Installer :
    "Windows could not format the partition on disk 0. The error occured during the preparation of system volume.Error code: 0x80042425"

    That's the starting point for me to play with DISKPART...and to try to format my "System" EFI partition into FAT32.
    When I am launching the command "FILESYSTEM" on the "SYSTEM" partition (EFI type), I only got exFat,NTFS and RESF....No FAT32...I wonder what is going wrong there...
      My Computer

  4. Posts : 17,369
    Windows 11 Pro

    Boot from the Windows installation USB flash drive or DVD. When you get to the first screen, press Shift + F10. In the command prompt that opens run:

    list disk
    select disk x <Replace X with the disk number of the SSD, probably 0
    clean <this will erase everything on the selected drive
    convert GPT

    Then see if the installer will allow you to install to the unallocated space.
      My Computer

  5. Posts : 5
    Thread Starter

    Thks for your feedback NavyLCDR

    I did what you ask for without real conviction as I was playing with all these kind of trials for the last two days (nights in fact).
    Nevertheless, W10 is currently installing....So it seems to work...
    However (because an however akways exist) I have to add that in between :
    - I formatted my USB Key again using Rufus with following settings (which I had already tried) : PArtition GPT for UEFI + FAT32 Format
    - I've put on the key another w10 ISO
    And then I've done your actions....
    In conclusion I think I add an issue with the first W10 ISO but I am not sure I am willing to change again to see if it is really the root cause
    I come back to you in some minutes
      My Computer

  6. Posts : 5
    Thread Starter

    Finally I decided to check if the ISO what the root cause...
    I am formating another USB key with the old ISO to check...
    Let's see
      My Computer

  7. Posts : 5
    Thread Starter

    So coming back with some news.... Old ISO is still not working
    I've done the same procedure as the one proposed by Navy this time without success
    Looking at DISKPART FILESYSTEM for "System" partition with the old ISO brings back only 3 possibilities : RESF or NTFS or exFAT...One thing to notice is that my old ISO is using DiskPart version 10.0.15048.0

    With the new iso, no problem at all, looking at the same partition with DISKPART brought back 5 possibilities: RESF or NTFS or exFAT or FAT or FAT32 (Youpi !!!!!!)...For sure then it is possible to format the EFI partition in FAT32 and everythin runs well...
    One thing to notice is that on the new ISO DISKPART version is 10.0.14393.0 (so older than the Old ISO Diskpart version )...
    But at list it works...

    So to conclude. I don't think the method proposed by Navy is the solution for my problem....I still assume that my problem what link to the ISO I used to create the USB Key and particularly that the ISO used formerly what including a DISKPART version not compatible with my H/W configuration.

    My last W10 ISO version is an All-in-One Version based on V1607 release x64
    The Old ISO versio I used was an Insider Build 15048 x64 (so newer than the working ISO version which explains the differences with DiskPart)

    Hope it helps for people who have same problem as me....And finally thanks to Navy for his/her time
      My Computer


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