Question GRUB2 no longer detects any of the Windows OSes ?

[kellogs]

Hey,

My PC multiboot = Linux, Win XP, Win 8.1; Bootloader = GRUB2

Recently the motherboard gave in; replaced it without issues for Linux and win 8.1, but on Win XP I had no keyboard or mouse. Also, in Win XP I only booted once in normal mode, tried then all the other safe modes, etc - always a brief BSOD (unreadable) then restart.

So, i figured after reading through the interwebs, a WinXP repair ought to install appropriate mobo drivers and fix my issue. However, attempting the repair also ended up in a forever BSOD + restart loop.

I got stuck in this phase for a while, tried many things, best I could get was :

- somehow got grub2 to list a "Windows 8.1" entry which, when selected just gave me a stuck screen "Setting partition type to 0x7" and nothing else
- followed 3rd method from https://learn.microsoft.com/en-us/t...rformance/windows-boot-issues-troubleshooting ; this made it so MBR got populated with Win 8.1 and I was able to boot into it. Then put on Linux live CD, installed grub2, rebooted into local linux, same deal - grub2 would not find any Windows OS

LAtest deed was to fresh install Win XP on its partition; MBR bootloader was that of Win XP, presented two entries, both called "Microsoft Windows Professional" or similar; one of them would boot into the newly installed Win XP, the other attempts to resume the failed repair (and BSOD + restart, of course). And then installed grub2 from live CD again and... same deal, no Win OSes detected.

The way it used to be:
MBR: grub2
/dev/sda1: Win 8.1 bootloader (which could boot Win XP as well)
/dev/sda5: the rest of Linux bootloader

I think I need a way to undo whatever has been done so as to abort that failed repair. What do you think ?

 

[kellogs]

After long battles with Paragon product suite, I realize my backup was actually made with Norton Ghost :-o
So i have restored that Win XP partition. And i am able to boot all 3 OS'es, but not from HDD grub. In other ways.

1. HDD grub

Went to HDD linux and ran

update-grub

. It did not find any Windows OS. Then I have manually mkdir'ed

/var/lib/os-prober/mount

and re-run

update-grub

This time it got me a Windows 8.1 entry which, if selected to boot, got me stuck on a black screen saying only

"Setting partition type to 0x7"

2. Live CD grub

Booted a Linux Mint 19 CD, mounted, chrooted, update-grubbed. Now the Windows 8.1 entry loads Win XP's bootloader

How do I revert to the old situation where the "Windows 8.1" grub menu entry would chainload Win 8.1's bootloader which in turn could load both Win8.1 and Win XP ?

non-EFI bootloading

Thanks!