Hopefully it should not matter what the media is. It's a USB, but I've confirmed that grub is reading from it : I can "ls" the files on it and find the EFI binary that way.
I guess I'm looking for a little more info on what chainloader does. My firmware cannot read the image; I believe that is because of the UDF filesystem. However grub can. I'm a little unclear on whether the chainloader somehow asks the firmware to load the EFI binary or runs it itself. Otherwise I don't know why grub can see this file (ls the file) but not run it. On Thu, 19 Oct 2023 at 16:55, Randy Goldenberg <[email protected]> wrote: > According to the link you provided, the ISO file can be used to > create installation media using a USB flash drive or DVD. In the "subject" > field of your email you refer to "MS Windows installer DVD", but in the > body of your message you refer to "MS Windows Installer (on USB)". > > Please clarify what your boot media is, and describe how you created it. > > On Thu, Oct 19, 2023 at 2:36 AM Philip Couling <[email protected]> wrote: > >> Hi >> >> Is there any reason why I can't chainload an MS Windows Installer (on >> USB)? Currently when I try this I get "UnknownError" when I type "boot" >> at >> the grub command line. >> >> The MS Windows ISOs are a bit weird: found here: >> https://www.microsoft.com/en-gb/software-download/windows10ISO >> >> They are not partitioned and have a UDF filesystem instead of ISO 9660 or >> FAT32. So my hardware cannot directly boot this. But I was assuming that >> all I would need to do would be ask grub to chainload the ISO as it has a >> UDF driver. >> >> I can read the Windows Boot media after I "insmod udf" and then >> "chainloader /efi/boot/bootx64.efi" which results in the output >> "/EndEntire". But when I then type "boot" I get "UnknownError". >> >> Has anyone experienced this? Any ideas about what isn't working? I freely >> admit it could be a Microsoft weirdness that requires their input, I just >> wanted to exhaust options here first. >> >> Thanks >> >
