WARNING: If you fail to do this correctly you could lose / delete data on the drive.
This is a quick guide to help people out (mainly myself when I forget how to do this), especially since the rise of Windows 10. At first I thought to look online to see if there was anyone else documenting this, especially where my windows installation is setup with UEFI. After sometime, I noticed a trend of people dual booting with Ubuntu and Windows 10, and that's cool if you're into that. However I tend to run with Fedora, and felt a bit stumped by some of the blogs and guides online.
Firstly, at lot of them were dual booting with an older version of Windows (7, or 8, or 8.1).
Secondly, all of the guides seemed to lack information, as I was expecting to need to do something with the BIOS or modifying this and that to get them to be able to dual boot.
It just seemed too easy... and it is just that easy.
The steps I'm listing are the steps I had to take to get this working for myself, while there may be some differences depending on the operating system most of it will remain the same or very similar.
So the steps to do a dual boot starting from nothing kinda go like this...
- Check your system's boot setting (choose either legacy BIOS or EFI), it does matter as this will affect the installation of the dual boot, I found you cannot really mix and match standard BIOS and EFI in dual boot without getting a headache or accidentally deleting the boot partition. Most modern GNU/Linux should be able to support EFI. I went with EFI
- Reboot the computer into a Windows installation media.
- Install Windows on the disk. Just let it gobble the entire disk, using the automatic settings.
- Once Windows is installed, and you are logged in, go in and shrink the disk using Window's built in Disk Management.
- Restart the computer and boot into a Fedora (or other) installation media.
- Setup the system language, date/time, blah blah blah, and then click onto disks.
- Select the disk you want to install on (this would show the physical disk, listing the free disk beneath). Just let Fedora (or whatever you like) to automagically set up the disk.
- Let Fedora install.
- Make sure you can reboot and log back into Windows and back into Fedora.
You may be wondering why...because I'm lazy and just want it to work.
You could use advanced options to manually configure the disk, but if you are doing that then this guide is probably a bit basic for you.
All done.
Now if you have installed/re-installed a few times, because you messed up, like I did, you may want to look into efibootmgr (from a Linux shell) just to clean up and tidy your EFI boot settings.