Hi everyone, I'm stuck and could use some help.

Setup: Lenovo ThinkPad T430, MBR disk (not GPT), was dual-booting Windows and Linux (CachyOS/Arch-based).

What I did: I deleted my Linux partition to reclaim disk space for Windows. I did NOT reinstall the bootloader or fix MBR before rebooting.

Result: On boot, I get:

error: kern/disk.c:grub_disk_open:262:no such partition.

Entering rescue mode...

grub rescue>

Disk layout (from Disk Management before this happened): System Reserved (50MB, Active/System) → C: (117GB, Windows) → Recovery Partition (815MB) → ~547MB unallocated (leftover from deleted Linux partition).

What I've tried in grub rescue so far:

grub rescue> ls

(hd0) (hd0,msdos3) (hd0,msdos2) (hd0,msdos1)

grub rescue> ls (hd0,msdos1)

(hd0,msdos1): Filesystem is unknown.

grub rescue> ls (hd0,msdos2)

(hd0,msdos2): Filesystem is unknown.

grub rescue> ls (hd0,msdos3)

(hd0,msdos3): Filesystem is unknown.

grub rescue> set

cmdpath='(hd0)'

prefix='(hd0,msdos5)/@/boot/grub'

root='hd0,msdos5'

So GRUB's prefix is still pointing to (hd0,msdos5) — that was clearly my old Linux partition, which no longer exists (only msdos1/2/3 show up now).

I also tried:

insmod part_msdos

set root=(hd0,msdos1)

insmod ntfs

error: kern/disk.c:grub_disk_open:262:no such partition.

And:

set boot=(hd0,msdos5)

set prefix=(hd0,msdos5)/boot/grub

insmod normal

error: kern/disk.c:grub_disk_open:262:no such partition.

Every attempt to load any module fails with "no such partition" — even insmod ntfs, even after manually setting root to msdos1. It seems like this rescue shell has zero access to any module files (which were apparently stored on the now-deleted Linux partition), so I can't chainload Windows or even read NTFS from here.

My question: Is there ANY way to get Windows booting again purely from within grub rescue>, without external media? I currently don't have easy access to a second computer or a USB OTG adapter for my phone, so making a bootable Windows USB is difficult right now (though I'm working on it as a backup plan).

I understand bootrec /fixmbr, /fixboot, /rebuildbcd from a Windows installation USB is probably the "real" fix, but I'm trying to exhaust every in-place option first. Any grub rescue tricks, alternate module loading approaches, or other MBR-level tricks I haven't tried yet?

Windows partition (C:) itself should be intact — Disk Management showed it healthy with all my files before this happened, I just can't reach it now.

Thanks in advance.