Many Windows users who have upgraded to Windows 10 from an older version of the Operating System experience an issue where their computers simply can’t download and install Windows Updates. Windows Updates come with a plethora of different improvements and fixes, and not being able to download and install them is a pretty significant issue. Users affected by this issue see the following error message when their computer attempts to try and download Windows Updates via Windows Update:
“Windows 10 couldn’t be installed. Windows can’t be installed because this PC has an unsupported disk layout for UEFI firmware.”
Here’s the whole shebang behind this problem: This problem is almost always seen in computers that have both UEFI and BIOS firmware (they are basically hybrids), and this problem is caused because Windows 10 – and, by extension, any Windows Updates for Windows 10 – can’t be installed on an MBR (Master Boot Record) disk on a UEFI computer (even if that computer is only half-UEFI) and can only be installed on a GPT (GUID Partition Table) disk on such a computer. Most users who have older versions of Windows installed on MBR disks can successfully upgrade to Windows 10, but once they do, problems such as this one arise.
UEFI firmware is the latest and greatest in computer firmware and is designed to gradually replace BIOS completely. On the other hand, GPT is the latest and greatest partitioning scheme for Hard Disks and is meant to replace MBR. GPT and UEFI are both associated with each other as Windows 10 – and Windows Updates for Windows 10 – can only be installed on a computer with UEFI firmware if they are installed on a GPT disk.
Affected users see the error message described above because their computers are trying to install Windows Updates on an at least half-UEFI computer, but the HDD or SSD that their instance of Windows 10 is installed on has an MBR layout and not a GPT layout. The simple solution to this problem would be to change the layout of the HDD or SSD in question to GPT, but doing so on a disk that has Windows installed on it has a pretty high chance of corrupting the instance of Windows installed on it and making the disk entirely unbootable.
That being the case, the most viable solution to this issue is to clean-install Windows 10 from scratch, and while doing so, formatting the entire HDD or SSD in question so that it is converted to GPT during the installation of a fresh instance of Windows 10 on it. Since the entire HDD/SSD that your current instance of Windows 10 is installed on will be wiped clean in the process, you should back up any and all important data stored on it. To do so, you can simply create a system image of your entire computer and then restore it once you have successfully clean-installed Windows 10, but if you don’t know how to create a system image, simply move any and all files you don’t want to lose to an external storage device (such as an external HDD/SSD or USB flash drive) and then restore them and reinstall all of your installed applications and programs following the clean-install.
In order to clean-install Windows 10 on your computer, simply follow this guide. However, during the clean-install, when you get to the ‘Where do you want to install Windows?’ screen, complete the following steps:
One by one, click on each and every single one of the partitions of the HDD/SSD that your current instance of Windows 10 is installed on to select them, and then click on Delete to delete them.
Once you have deleted all of the partitions of the HDD/SSD in question, the disk will show up as Drive X Unallocated Space (X being the number assigned to the disk) with its total size being the entirety of the disk. Click on Drive X Unallocated Space to select it and then click on Next.
Once you do so and go through with the clean-installation of Windows 10, Windows will automatically turn the unallocated space on the disk into actual partitions, and the disk will also be converted to GPT along the way.