How To: Dual-boot Windows 10 with Windows 7 or 8.1

Dual Boot

As much as I am currently enjoying Windows 10, the operating system is flawed in many ways. That is obviously the case with any new major release of an operating system so many people hold back with the upgrade until they are confident the initial issues have been resolved. But if you want to get the best of both worlds, meaning you can have your cake and eat it too, you can simply dual-boot Windows 10 with your current Windows 7 or 8.1 system without having to worry about messing up your one and only computer. The process may be a bit complicated for users who have never tried dual-booting before but we are going to take it step-by-step so follow the post closely and you should have no issues whatsoever.

With that said, I strongly recommend that you backup your computer before proceeding. One of the available options is to create a system image as we have shown you for Windows 7 and Windows 8.1.

Step #1: Resize your partition

In order to dual-boot, your hard drive needs to be partitioned and a part of it dedicated to the shrine of Windows 10. If you happen to have two hard drives in your system, you can completely skip this part as you can install Windows 10 on the second hard drive. If not, you are going to have to use the Disk Management tool to resize your main partition and make some space for the new OS.

1. Open Disk Management. The easiest way to do that is to open your Start Menu, type diskmgmt.msc and hit Enter.

2. Once the utility opens, locate the system partition. By default, this should be the (C:) volume. When you find the correct one, right click on it and select the option that reads Shrink Volume.

Disk Management Shrink Volume

3. Windows 10 requires about 20GB of free space so if you merely want to try the operating system, I suggest you create a new partition of at least 30GB. This should give you enough space to try out some apps, browse every area of the OS and familiarize yourself with it. Of course, you can go ahead and dedicate as much space as you want, especially if you have a hard drive with a large capacity.

Step #2: Get Windows 10

Windows 10 Setup Tool

Go to Microsoft’s official Download Windows 10 site and grab the version of the tool which is appropriate for your system. Choose the option that reads Create installation media for another PC, select the language and version you want and click on Next. You will now need to insert a USB flash drive or a DVD so that the tool can put Windows 10 in there. The only requirement for the USB drive is that it is at least 3GB but that should not be a problem nowadays.

Step #3: Install Windows 10

Once the whole process is over, leave the USB drive or the DVD inside your computer and restart it. You should get redirected to the Windows 10 installation but if that does not happen, you probably need to change the boot order in your BIOS. We have a guide on how to enter the BIOS in most computers as well as more specific instructions for Windows 8.1 PCs with the new UEFI BIOS firmware. Once you enter the BIOS, look for the Boot menu and place your DVD or Flash drive to the very top. Do not touch anything else and make sure to save before you exit.

Windows Setup

When you finally arrive to the Windows Setup screen, click on the Install now button, confirm the agreement if needed and select the Custom installation option. This is absolutely crucial as it is the only way you can actually dual-boot. The next screen should ask you “Where do you want to install Windows?” so select the Unallocated Space partition which is what you created in Step 1. With that option selected, click on New and then on Apply to use all the available space.

The installer will automatically create a new partition and select it or you so just click on Next and let the tool do its job. This will take a while so just leave it there, go about your business and once you come back, you will be able to use Windows 10.

Step #4: Dual-booting (or choosing your favorite child)

Dual-boot Options

Now that you are the proud owner of two operating systems, your PC will ask you whether you want to go into Windows 10 or Windows 7 each time you boot it up. I highly recommend you click on the Change defaults or choose other options link because that way you can select a default operating system and set a timer so that your PC can automatically boot into that without you having to make a selection first.

Well that about does it. If you have any questions or run into any problems, drop a comment down below and I’d be more than happy to help you out!