Windows Partition Visible in Ubuntu But Not Visible in Bios or Grub

tr flag

I use a dual-boot Ubuntu 20.04 and Windows 10 machine. However, after a recent Timeshift rollback of my Ubuntu installation. My windows 10 partition disappeared in both grub and bios. However, I can still use Nautilus to open the drive and view its files (Nautilius will -not- mount the drive on the left-hand side). UEFI, secure boot disabled, fast boot disabled.

I've tried: sudo os-prober & update-grub but they didn't work.

When I execute lsblk it shows:

nvme0n1                                       259:0    0 238.5G  0 disk  
├─nvme0n1p1                                   259:1    0   100M  0 part  /boot/efi
├─nvme0n1p2                                   259:2    0    16M  0 part  
├─nvme0n1p3                                   259:3    0 120.2G  0 part  
├─nvme0n1p4                                   259:4    0     1G  0 part  
├─nvme0n1p5                                   259:5    0  93.1G  0 part  /
└─nvme0n1p6                                   259:6    0  24.1G  0 part  [SWAP]

Where nvme0n1p3 is my Windows Partition.

How can I get Grub / Bios to recognize my Win10 partition again?

tr flag

boot the machine using a Windows USB key, go to "command prompt", enter (separately):

bootrec.exe /fixmbr
bootrec.exe /rebuildbcd

reboot & allow Windows to scan / repair the drive.

login into windows and make sure everything is working.

reboot and enter bios as necessary disable: fast boot & secure boot, then select ubuntu as the first boot disk, exit bios.

Boot into ubuntu and run os-prober which should successfully locate the new repaired windows partiition.

Then run update-grub and reboot.

Windows should be back in the grub menu. :-)


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