If your PC has multiple drives, make sure you're deleting the partitions on the correct drive. The drive will show a single area of unallocated space. On the Where do you want to install Windows? screen, select each of the partitions on the drive where you're installing Windows, and select Delete. In Windows setup, When choosing an installation type select Custom. For more info, see Boot to UEFI Mode or Legacy BIOS mode.

Turn off the PC, and put in the Windows installation USB key or DVD.īoot the PC to the USB key or DVD in UEFI mode. Reformatting the drive using a different partition style Use Windows setup to Wipe and convert the drive The GPT drive format lets you set up drives that are larger than 4 terabytes (TB), and lets you easily set up as many partitions as you need. It's also difficult to set up more than four partitions. However, the basic MBR drive format does not support drives over 4TB. This version of BIOS was developed in the 1970s and provides compatibility to a variety of older equipment and network configurations, and requires a drive that uses the MBR drive format. Many PCs are ready to use UEFI, but include a compatibility support module (CSM) that is set up to use the legacy version of BIOS. To boot your PC in UEFI mode, you'll need to use a drive formatted using the GPT drive format. Many PCs now include the ability to use the UEFI version of BIOS, which can speed up boot and shutdown times and can provide additional security advantages. Reformatting will erase all the data on the drive. You can preserve your data and convert the drive using the MBR2GPT tool, or you can choose to reformat the drive using the instructions below. This option lets you use the PC’s UEFI firmware features. For more info, see Boot to UEFI Mode or Legacy BIOS mode.Ĭonfigure your drive for UEFI by using the GPT partition style. This option lets you keep the existing partition style. Reboot the PC in legacy BIOS-compatibility mode. The selected disk is not of the GPT partition style, it’s because your PC is booted in UEFI mode, but your hard drive is not configured for UEFI mode. When installing Windows on UEFI-based PCs using Windows Setup, your hard drive partition style must be set up to support either UEFI mode or legacy BIOS-compatibility mode.įor example, if you receive the error message: Windows cannot be installed to this disk.

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