This post shows how to dual-boot Ubuntu 16.10 and Windows 10 on a computer with UEFI firmware and on a single hard drive. The computer used for this article is an HP 250 G5 laptop with Secure Boot disabled.

First Step – Get Your Windows 10 Computer Ready

1. For a pain-free and successful operation of the sort that you’re about to undertake, it is recommended that you disable Secure Boot (Restricted Boot). How this is done depends on your computer, but if you have the same HP 250 G5 laptop I used for this tutorial, see this article. Owners of a Lenovo G50 laptop should consult this guide.

2. From the BIOS or UEFI setup utility, configure the computer to boot from external media.

3. After that, you need to free up disk space from your computer by shrinking the C drive or other partition with enough free space on it. Getting that done is fairly simple by using Windows 10 partition manager. When completed, the partition should show partitions and free disk space similar to the one shown in Figure 1. Ubuntu 16.10 will be installed in the Unallocated disk space.

Windows 10 free disk space

Figure 1: Windows 10 partitions and the free disk space for installing Ubuntu 16.10

Download Ubuntu 16.10 and Create a Bootable USB Stick

The next step in this operation is to download an installation image of Ubuntu 16.10 desktop from here, then transfer it to a USB stick. From Windows 10, use this article as a guide to create a bootable USB stick of Ubuntu 16.10. And from any Linux distribution, the simplest method is to use the following command:

# This command assumes that you're executing it from your Download directory
# 
# /dev/sdb is the target USB stick. Yours might not be sdb, so verify before copying and pasting

sudo dd if=ubuntu-16.10-desktop-amd64.iso of=/dev/sdb bs=1M conv=sync

#

When you’ve finished creating the installation media, insert it into the appropriate port in your computer and reboot. In the next step, you’ll use that bootable USB stick to install Ubuntu 16.10 alongside Windows 10.

Dual-boot Ubuntu 16.10 With Windows 10

If the computer has been set up to boot from external media, you should see the Ubuntu 16.10 boot menu. One of the entries will be to boot into the Live desktop. I suggest you select that option, play around with the Live desktop, and if you’re satisfied, launch the installer by clicking on its icons on the dock or on the desktop.

After the installer starts, click through the first few steps until you get to the one shown in Figure 1. The installer should detect that Windows 10 is already installed and offer to install Ubuntu 16.10 alongside it. That’s great, but it will not create a separate partition for your files and folders.

Partition methods of Ubuntu 16.10 installer

Figure 1: Partition methods of Ubuntu 16.10 installer

For that to happen, you’ll have to select the Something else option, then click on the Continue button to move to the next step.

Something else option  of Ubuntu 16.10 installer

Figure 2: Something else option of Ubuntu 16.10 installer

That next step shows the so-called advanced partitioning tool, where you’ll see all the partitions detected by the installer. Of the existing Windows 10 partitions, the one of interest here is the one that has efi in the Type column and Windows Boot Manager in the System column. That is the EFI System Partition, where the boot loader files will be installed. To start creating partitions, select the free space, then click the + button.

Ubuntu 16.10 advanced partition tool

Figure 3: Advanced partitioning tool of Ubuntu 16.10

That should bring up the installer’s partition editor. For each partition, you only need to specify the size, the file system (from the Use as menu) and the mount point. For partitions other than the one that will be used as swap, stick with the default file system – Ext4 journaling file system.

Ubuntu 16.10 partition editor

Figure 4: Ubuntu 16.10 partition editor

So let’s start by creating the root partition. For size, any value higher than 20 GB will do. From the Mount point, select /. Click OK.

Ubuntu 16.10 root partition

Figure 5: Ubuntu 16.10 root partition

The next partition will be mounted at /home. This is the partition that will hold all your files and folders, so assign most of the available disk space to it. When you’re finished setting it up, click OK.

Ubuntu 16.10 home partition

Figure 6: Ubuntu 16.10 home partition

For the partition that will be used as swap, a size of 2000 MB (2 GB) to 4000 MB (4 GB) should be enough. From Use as, select swap area. OK.

Ubuntu 16.10 swap partition

Figure 7: Ubuntu 16.10 swap partition

After creating that last partition, you should be back in the main partitioning tool’s window for the last time. From the Device for boot loader installation, select the efi partition. On the system used for this article, that partition corresponds to /dev/sda2, that is, the second partition on the hard drive. Then click on the Install Now button to continue with the rest of the installation.

Ubuntu 16.10 advanced partition tool

Figure 8: Advanced partitioning tool of Ubuntu 16.10 after creating partitions

After installation has completed successfully, rebooting the computer should reboot into the GRUB menu. GRUB (Grand Unified Bootloader) is the boot loader used on virtually all Linux distributions. Aside from the entries for Ubuntu 16.10, it will also have one for Windows 10, which makes it possible to boot into Windows from the GRUB menu. Unfortunately, you can’t add an entry for Ubuntu 16.10 in the Windows Boot Manager menu, so it’s recommended that you make GRUB the default boot manager. To accomplish that, read this article.