How to Install and Remove a Windows‑Linux Dual‑Boot System Step‑by‑Step

1. Prepare a bootable Ubuntu USB

Use an 8 GB (or larger) USB drive, back up data, and format it later. Download the Ubuntu ISO (e.g., 18.04 or 16.04) from the official site:

https://www.ubuntu.com/download/desktop

http://releases.ubuntu.com/

Create the bootable USB with Rufus: open Rufus, select the ISO file, keep the default parameters, and click Start. Accept the default prompts.

2. Allocate disk space for Ubuntu

Open Windows Disk Management (Win+X → Disk Management) and shrink an existing non‑system partition (preferably the last one) to create at least 100 GB of free space.

Right‑click the selected volume → Compress Volume and specify the desired size.

3. Install Ubuntu

Insert the bootable USB, reboot, and select the entry labeled Ubuntu from the boot menu.

When the installer starts, choose Install Ubuntu . If you have internet, enable the option to download updates during installation.

Select Something else to manually partition the free space. Recommended partition layout (create each as a logical partition within the free space):

/ – 150‑200 GB, ext4, root filesystem

/home – as large as possible, ext4, user data

/boot – 1 GB, ext4, boot loader files

swap – size = 2 × RAM (or equal to RAM if RAM > 8 GB), swap area

After creating the partitions, click Install Now and select the device for the boot loader (usually /dev/sda).

4. (Optional) Adjust boot order

If Windows remains the default boot option, install EasyBCD in Windows and move the Ubuntu entry to the top of the list.

Download link (subject to change): https://pan.baidu.com/s/1slPiDZ3 (password: z3r7)

5. Uninstall Ubuntu and restore Windows

5.1 Delete Ubuntu partitions

In Windows Disk Management, right‑click each Ubuntu partition and choose Delete Volume . Then extend the original Windows partition (e.g., D:) to reclaim the space.

5.2 Remove Ubuntu boot entry

Open an elevated command prompt and run: diskpart Then execute the following commands (adjust disk/partition numbers as needed):

list disk
select disk 0
list partition
select partition 1   // EFI system partition
assign letter=P

Mount the EFI partition (now drive P:). Using a file manager with administrator rights (e.g., Total Commander), navigate to P:\EFI\ubuntu and delete the folder.

Reboot. The GRUB menu should disappear, leaving Windows as the sole boot option.

References

Original tutorial: https://blog.csdn.net/fanxueya1322/article/details/90205143

Additional sources: https://blog.csdn.net/flyyufenfei/article/details/79187656, https://blog.csdn.net/u012052268/article/details/77145427