Win 10 Rollback utility, grub rescue is all I get?

Hi! Have a PC which was upgraded from Win 8.1 to Win10 and it didn't go well computer can no longer boot into Windows (even in Safe mode it fails to boot). So, I need a way to rollback the Win 10 update.... downloaded your Win 10 Rollback Utility file, burned it to CD successfully, put CD in computer and booted to it. Appears to boot ok to the CD but I only get the following:

Errror: Invalid arch independent ELF magic.
grub rescue >

I typed in LS and the following was listed:
(hd0, cd)
I then typed in set and the following was listed:

Now, I'm no grub guru but it appears the boot image is incorrectly detecting the hard drive. There is only the 1 hard drive in this computer and it should be hd0 and it's only got 1 partition on it (no dual boot or anything, very straightforward). So why is the grub config setting it to hd31 then?

So I'm stuck at this point I don't know enough about grub to debug this problem. Any thoughts? I checked the cd contents and all the folders appear to be there I burned it as an iso image with Nero software. Since it seems the computer is in fact booting from the cd correctly and I can read the cd contents on my primary workstation ok, but grub isn't configuring right, there should be no problem with the boot-ness of the cd itself.


- Michael
Well... since there's been no reply so far, I decided to try this Windows 10 Rollback Utility boot CD on some other computers I have here (that don't have any boot issues), and found on ever computer I booted it on it only goes to Grub Rescue. That's it. So there is definitely something wrong with the grub installation in the iso file image.

I also noticed no matter how many hard drives a computer has (I have some with a single drive single partition, and 1 with dual physical hard drives) the set command always shows Prefix and Root are set to hd31 (like hd31 is hard coded in the grub install for some reason). Clearly that isn't going to work right for most people!

Ya'll need to check your utility, it just does not work correctly as far as I'm able to tell. I only have so many computers and it fails on every single one after all....

- Michael


Mostly Harmless
Staff member
Hi Michael,

Did you burn this with Nero? It's famous for having issues with non-Windows bootable CDs. Please try these instructions instead: