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--- grub_repair [2025/03/13 06:09] – created kkaragoz
+++ grub_repair [2025/03/13 06:53] (current) – kkaragoz
@@ Line 1: / Line 1: @@
 GRUB Repair Guide
-Add Missing Windows 11 Entry
+Add Missing Windows 11 Entry (Tested on Debian 12 + Windows 11 UEFI systems)
-(Tested on Debian 12 + Windows 11 UEFI systems)
+==== 1. Basic Fix (90% Success Rate) ====
+<code bash>
+sudo apt install os-prober
+sudo update-grub
+</code>
+==== 2. Manual GRUB Entry (For NVMe Drivers) ====
+== a. Identify Windows EFI Partition ==
+<code bash>
+sudo lsblk -o NAME,FSTYPE,SIZE,MOUNTPOINT
+</code>
+Look for:
+  * FAT32 partition (usually 100-500MB)
+  * Example output: nvme0n1p1 vfat 100M /boot/efi
+== b. Create Custom Entry ==
+<code bash>
+sudo nano /etc/grubd/40_custom
+</code>
+Add:
+<code bash>
+menuentry "Windows 11" {
+   insmod part_gpt
+   insmod chain
+   insmod ntfs
+   set root=(hd0,gpt1) #hd0 = first disk, gpt1 = first partition
+   chainloader /EFI/Microsoft/Boot/bootmgfw/efi
+}
+</code>
+== c. Apply Changes ==
+<code bash>
+sudo update-grub
+sudo reboot
+</code>
+==== 3. Verify UEFI Mode ====
+Linux should show UEFI vars:
+<code bash>
+ls /sys/firmware/efi/efivars
+</code>
+Windows partition should have EFI files:
+<code bash>
+sudo ls /boot/efi/EFI/Microsoft/Boot
+</code>
+Expected file is **bootmgfw.efi**
+Troubleshooting Table
+"hd0 not found"
+  - Replace hd0 with actual disk number
+  - Use lsblk to confirm partition numbers
+No bootmgfw.efi
+  - Check Windows installation mode (must be UEFI)
+  - Disable "Secure Boot"
+GRUB menu not showing
+  - Hold Shift during boot
+  - Run sudo grub-install /dev/nvme0n1
-Basic Fix (90% Success Rate)