Dual Boot Ubuntu and Windows 10

UEFI BIOS Dual Boot

For computers with Unified Extensible Firmware Interface (UEFI)

1. Determine if your computer has UEFI - Press Windows Key + R and type "msinfo32"
2. Within "System Summary" look for "BIOS Mode" and it should say "UEFI", if it says "Legacy" then this procedure is not for you.

THIS GUIDE IS ONLY FOR UEFI BIOS COMPUTERS

Here's what you need to do:

1. Install Windows or if Windows is already installed make sure there's room on the hard drive for Linux, if not then shrink the windows partition
2. install Ubuntu - choose to "Install Ubuntu alongside Windows Boot Manager."

Legacy BIOS Dual Boot

For computers with Standard BIOS.

Here's what you need to do:

1. Install Windows or if Windows is already installed make sure there's room on the hard drive for Linux, if not then shrink the windows partition
2. install Ubuntu - choose to "Install Ubuntu alongside Windows" - SEE FULL INSTALL DETAILS BELOW
3. Edit the boot order to make sure Ubuntu can boot

Turn off fast boot
Turn off secure boot
Install Ubuntu

FULL INSTALL DETAILS

Here is how you install Ubuntu: Boot from the Ubuntu boot drive be it disc or USB stick. Booting into Ubuntu on a computer with a standard BIOS is a lot simpler than UEFI based machines.

An install dialog will appear with two options, TRY UBUNTU or INSTALL UBUNTU. You need to choose the TRY UBUNTU.

If not connected to the Internet it is recommended that you connect so that you can download updates and 3rd party software during the install. You can check this within the X environment before proceeding with the install.

After the Ubuntu environment loads the desktop you will see an icon that labeled "Install Ubuntu." This is the route we are going to take to do the installation. The "Installation Type" screen lets you decide whether you want to install Ubuntu alongside Windows or over the top. Choose the "Install Ubuntu alongside Windows" option.

Select the rest of the desired install options and complete the installation. When the process has finished you will have the options to continue test or to restart now. Click the "Restart Now" option. You will be asked to remove the USB drive and press enter. Now when your computer reboots you will have options to boot into Windows 10 or Ubuntu.

Resize "shrink" the Windows Partition

This step is relative to both Standard and UEFI BIOS. If Windows is already installed and occupying all of the available hard drive space, then it needs to be reduced to free up space for the Linux partitions.

Windows 10 built-in Disk Management has the ability to shrink volume and extend volume.

Press the Windows Key + R and type:

diskmgmt.msc

In the Windows "Disk Management" tool click the "Create and Format Hard Disk Partitions" option. The top pane shows you a list of your partitions, the bottom one shows you a graphical representation of your storage devices.

Right-click a partition and select Shrink Volume to resize it. You can only shrink a partition if there is enough free space. The partition you will want to shrink is the one that says it is an NTFS partition which is both active and primary.

If the filesystem is fragmented, there are system protection backup files in the way, or the swap file is in the way then you will be limited on how much you can shrink the partition even though there is free space greater than what is available. For tips on how to make it possible to further shrink the partition see How to Shrink a Windows 10 Partition.

Backup Image of Windows

You can create a backup image of Windows before you start so if you want to restore things in the event something goes wrong then you have that option.

Control Panel -> System and Security -> File History

Look in the bottom left of the File History dialog box and click "System Image Backup."

See: Windows System Image Backup