Unable to boot from USB / No EFI partition

Mart.. -  
 Ludodufigolu -
Hello,
the Windows 10 on my laptop won't start anymore (error 0xC0000185 when the PC tries to boot from the "Windows Boot Manager"). I looked online and saw that it was due to a problem with the EFI partition and that I needed to use the Windows repair tool by booting from the USB key containing it.
So I created the USB key (NTFS) with the Windows 10 ISO on it to repair it. I then went into the BIOS to change the boot order and set the USB drive to boot first (I assume it's "UEFI: generic flash disk 8.07" :)
. However, when the PC tries to boot from the USB key, an error appears saying "could not locate '\efi\boot\bootia32.efi':[14] Not Found". And now I don't know what to do, I need to boot from my USB drive to repair Windows.

So I am calling on professionals for help :) If anyone has a solution, I'm all ears :)
Thank you

Configuration: Linux / Firefox 65.0

3 réponses

heraultais34600 Posted messages 776 Status Membre 97
 
Good evening,
Are you sure that your USB drive is "bootable"? At worst, if your computer has a CD/DVD drive, create a medium on a DVD, modify the BIOS accordingly, and boot from the DVD.
Have a good evening.
0
Mart..
 
Good evening, thank you for your reply.
The key is indeed bootable; I tested it on another PC and it worked. I don't have a CD/DVD drive on my PC since it's an Asus laptop (an Asus Transformer Book tablet/computer) and there's only one USB port, so I can't do anything else.
0
heraultais34600 Posted messages 776 Status Membre 97
 
Hello,
You say: "there's only one USB port so I can't do anything else."
Yes, there is always a way, try to get (or buy) an external CD/DVD drive. From this external device, once the BIOS is set to boot from the CD/DVD drive, you will be able to install the system.
Have a nice day.
0
Mart..
 
Hello
Indeed, the external CD/DVD drive would be a way, but I'm afraid I still won't be able to boot from the disk because it will still be connected via USB like my flash drive, and the problem doesn't come from the flash drive but from not being able to boot from something connected via USB. Because in the BIOS, even with the flash drive plugged in, the error is that there is no EFI, so I suppose it will be the same for the CD/DVD drive.
0
thev Posted messages 2007 Registration date   Status Membre Last intervention   722
 
Hello,

You must have an Asus T100 tablet. A USB boot key must be in Windows 32 bits and in FAT32 format.
Your current key must be in Windows 64 bits.
How did you create it?
0
Mart..
 
Hello
Indeed, it is a T100 type tablet (T100TAM to be precise). I created my USB key on a PC running Linux using Woeusb by following a tutorial online. My Windows 10 ISO is 64 bits :/ I will try to recreate it as you suggested. But will that resolve my EFI partition issue? Will the PC be able to boot from the USB key?
0
thev Posted messages 2007 Registration date   Status Membre Last intervention   722
 
With a 64-bit Windows ISO, you won't get there because you need a 32-bit Windows ISO.
I will assist you with the custom ISO W32 bits key I developed, which contains a repair script for the EFI partition. Everything is explained in the .txt file included in the .zip for which I'm providing you the link

https://drive.google.com/file/d/1rcN_BRbs7lwNzoi475m2m9Llq8XC41W5/view?usp=sharing
0
Mart..
 
Thank you for your help.
I read the text file you gave me. The only problem is that the only PC I can use to create my key is running Linux, so the Rufus program doesn’t work. I have thus reused WoeUSB to put the 32-bit Windows ISO on the key after formatting it to FAT32 with cfdisk in Linux. It's in progress, I hope it’s going to work.
0
Mart..
 
Well, I solved my problem. It was indeed due to the format of the USB drive and the ISO. I set my USB drive to FAT32 and the ISO to 32-bit and it works.
Thank you for getting back to me :)
0
Ludodufigolu
 
Hello, I'm not sure I understood everything. For my part, I'm looking to install Windows 10 x64 on a laptop that runs on Ubuntu 64bits. When I enter the BIOS, my USB drive is detected as "UEFI:Verbatim, Partition 1" but when I try to boot from it, nothing happens :-(
Thank you in advance for your help.
0