How to Fix: Windows Cannot be Installed: the Selected Disk is GPT / MBR

Infopackets Reader Sarah H. writes:

" Dear Dennis,

A few days ago, my PC got stuck updating Windows 10 (for over 30 minutes), so I pulled the power cord out. After that, Windows wouldn't boot to the desktop. It would give me blue screen of death (BSOD), then reboot, then BSOD, ad infinitum. I knew it was stuck in a reboot loop, so I decided to install Windows 10 again. During the Windows 10 setup, it asks me to select where to install Windows. I selected the C drive, but I get an error message that says: 'Windows cannot be installed to this disk. The selected disk is of the GPT partition style'. Windows setup will not let me continue. How can I install Windows 10 onto my C drive without losing data / formatting the drive? "

My response:

First of all - you should never, ever pull the power or forcefully shut down a machine during a Windows Update, or you risk corrupting Windows. What might happen next is that Windows becomes unbootable, just as you described.

The reason why you are receiving the error message "Windows cannot be installed to this disk. The selected disk is of the GPT partition style" is because the Windows DVD / USB drive booted in Legacy BIOS Mode, but the hard disk was previously formatted using UEFI mode. The easiest solution is to set the computer to boot from DVD / USB in UEFI mode using a Boot Option Menu (if your computer supports it); if not, you will need to go into the BIOS and set it to UEFI mode.

The same issue will occur if you boot from UEFI and try to install Windows on a disk that has MBR partition scheme. In that case, the error message would be "Windows cannot be installed to this disk. The selected disk has an MBR partition table." In this case, you need to boot from using Legacy Mode to install Windows using MBR partition scheme.

In either case: I'll explain more about the process below.

How to Boot in Legacy or UEFI Mode / Enter BIOS

When using Legacy Mode, the hard drive that boots Windows uses MBR (master boot record) partition scheme. Conversely, when the system is configured for UEFI Mode, the hard drive that boots Windows is configured using the GPT (GUID Partition Table) partition scheme.

MBR has been around since the 1983, whereas UEFI (Unified Extensible Firmware Interface) has been around since 2005 or so, but didn't really catch on for a few years after that. The major difference is that Legacy Mode supports up to 4 primary partitions and partition sizes of up to 2TB of data, while GPT does not have these limitations.

• To use the GPT partition scheme: Turn on the computer and enter the BIOS, then go to (usually) the "Boot" menu and change from Legacy and UEFI. If you don't see the option in the Boot menu, it may be somewhere else - keep looking. Refer to this pic which shows the boot menu and changing the option from UEFI to Legacy as an example.
   
• To use the MBR partition scheme: Turn on the computer and enter the BIOS, then go to (usually) the "Boot" menu and change from UEFI to Legacy. If you don't see the option in the Boot menu, it may be somewhere else - keep looking. Refer to this pic which shows the boot menu and changing the option from UEFI to Legacy as an example.

You can also refer to this video which shows how to enter the BIOS using an Acer Laptop (which uses the F2 key to enter the BIOS).

Can't Boot in UEFI / Legacy Mode? Here's Some Alternatives

Adjusting the computer to boot from Legacy to UEFI and vice versa can be a major technical barrier if you're not computer savvy, mostly because (a) the key to enter BIOS / Setup / Boot Menu varies from manufacturer, and (b) pressing the key to enter the BIOS / Setup/ Boot Menu must be timed exactly at the right time, or the computer simply keeps booting as usual. This can be incredibly frustrating if you don't time it right, or if you aren't pressing the right key!

My advice is: search Google for the make and model of your computer and find its manual on the manufacturer's website. Search the manual for "entering BIOS mode", or such, then find out which key is used to enter BIOS. Typical keys are DEL, F2, F12 - but as I mentioned, it varies from manufacturer.

Once you know which key it is, press that key 100 times non-stop the moment you turn the computer on, and hopefully you will get into the BIOS. Once in the BIOS, go to the Boot menu (or similar) and make the adjustment from Legacy to UEFI or vice versa. Once again, you can also watch this video, which shows how to enter the BIOS and change boot from UEFI to Legacy as an example.

If you can't boot the computer in UEFI / Legacy mode due to issues I've mentioned above, there are a few options:

1. Use another computer to create a bootable rescue media, so that you can backup your existing hard drive. For this I suggest using Macrium Reflect Free; once installed, click launch the program, then click Other Tasks -> Create Rescue Media menu. When that is finished, insert the bootable rescue media into the computer that can't boot and proceed to backup onto an external hard drive. Proceed to Step #3 to wipe the drive after backup has been completed.
    
2. If option #1 doesn't work (because Macrium Reflect doesn't support your hardware), another option is to take the hard drive out of the computer that can't boot and attach it to another computer. When complete, perform a backup using Macrium Reflect on the working computer. You can store the backup on this computer (if you have enough space), or an external drive, for example. Proceed to Step #3 to wipe the drive after backup has been completed.
    
3. Another option is to continue installing Windows by wiping the existing hard drive clean. To do so, select each hard drive partition and click the "Delete" link (pic) when it asks you "Where do you want to install Windows?" Keep doing this until you see a single "partition" with unallocated space, then click Next. Windows will configure the drive using MBR or GPT and begin installing Windows.

I hope that helps.

Additional 1-on-1 Support: From Dennis

If all of this is over your head and you can't get passed the "Windows cannot be installed to this disk. The selected disk is of the GPT partition style" error message - I can help using my remote desktop support service. Simply contact me, briefly describing the issue, and I will get back to you as soon as I can.

Got a Computer Question or Problem? Ask Dennis!

I need more computer questions. If you have a computer question -- or even a computer problem that needs fixing -- please email me with your question so that I can write more articles like this one. I can't promise I'll respond to all the messages I receive (depending on the volume), but I'll do my best.

About the author: Dennis Faas is the owner and operator of Infopackets.com. With over 30 years of computing experience, Dennis' areas of expertise are a broad range and include PC hardware, Microsoft Windows, Linux, network administration, and virtualization. Dennis holds a Bachelors degree in Computer Science (1999) and has authored 6 books on the topics of MS Windows and PC Security. If you like the advice you received on this page, please up-vote / Like this page and share it with friends. For technical support inquiries, Dennis can be reached via Live chat online this site using the Zopim Chat service (currently located at the bottom left of the screen); optionally, you can contact Dennis through the website contact form.