Removing Ubuntu from a Windows dual-boot is a three-step process. You should start by making the Windows Boot Manager the default boot loader. Then, you can boot to Windows and delete the Ubuntu partition. The final step is to delete the GRUB files from the system partition so that the Ubuntu entry no longer shows up when booting. We’ll cover this process with step-by-step instructions in this article. Change Boot Priority Setting the Windows Boot Manager to top priority in the boot order will minimize the chances of any boot-related errors. You can do this from your firmware settings, which you can access by pressing the BIOS Setup key shown on the screen when booting. Some machines may boot too fast for this. In that case, you have two options. If doing this from Windows, hold Shift when restarting or force-restart 3 times in a row. This’ll take you to the Windows Recovery Environment. Select Troubleshoot > Advanced options > UEFI Firmware Settings and click on Restart. If doing this from Linux, hold Shift or press Esc a few times when booting to access the GRUB menu. Select the Firmware Settings option there. In your firmware settings interface (BIOS/UEFI), go to the Boot tab. Move the Windows Boot Manager to the top of the boot order list. Then, press the key shown on the screen to save the changes and exit (usually F10). Delete Ubuntu Partition Upon exiting the firmware interface in the previous step, your PC should restart and boot to Windows. Open Disk Management there and configure the partitions as shown below: Press Win + R, type diskmgmt.msc, and press Enter to open the Disk Management console. Identify the Ubuntu partition(s) here. By default, they won’t have a drive letter or a recognizable filesystem. You can also check the partition sizes to identify them. Right-click the Ubuntu partition, select Delete volume, and press Yes to proceed. Repeat the same for the remaining Ubuntu partitions (if applicable). You have two options with the freed-up space. You can right-click an existing partition and select Extend Volume. This’ll append the free space to this partition. Or, you can right-click the unallocated space and select New Simple Volume to create a new partition. You can just proceed with the default options for this process; there’s no need to change anything. Remove GRUB Files The Linux bootloader (GRUB) files are stored in the system partition, which is not mounted by default. UEFI In the case of UEFI systems, you can follow the process shown below to remove those files. Press Win + R, type cmd, and press Ctrl + Shift + Enter to open an elevated command prompt window. Start the diskpart utility, then list and select your disk using the disk number (#). diskpart list disk sel disk 0 List the partitions on this disk. list part The partition with System in the Type section is the EFI System Partition here. Select this partition using the partition number #. sel part 1 Assign a drive letter to the EFI partition to mount it. assign letter=z exit Navigate to the Z:\EFI directory and list the contents. Z: cd EFI dir Finally, delete the Ubuntu folder here. rd /s ubuntu BIOS On legacy BIOS systems, hold Shift and restart. Alternatively, force-restart 3 times in a row to boot to the recovery environment. Select Troubleshoot > Advanced options > Command Prompt. This’ll launch the WinRE command prompt that’s run using the recovery image. Run the following commands to repair the boot sector: bootrec /fixmbrbootrec /fixbootbootrec /scanosbootrec /rebuildbcd