How to fix “the selected disk is of the GPT (or MBR) partition style”
This setup error is a mismatch between how the PC is booting and how the target disk is partitioned. Matching the two, or converting the disk, fixes it. Jump to your situation below or work through the methods in order.
By Neeraj Singh ~8 min Updated Jun 2026 88% found this helpful
Error message
Windows cannot be installed to this disk. The selected disk is of the GPT (or MBR) partition style.
Summary
During Windows setup, the selected disk is of the GPT partition style (or the MBR variant) is a mismatch between the firmware boot mode and the disk layout. UEFI mode requires a GPT disk, and legacy BIOS / CSM mode requires an MBR disk. If you boot the installer in UEFI but the target is MBR, or boot legacy with a GPT disk, setup refuses with this message. Windows 11 specifically needs UEFI and GPT. The fix is to make the two match: boot the installer in the mode that suits the disk, or, better for Windows 11, convert the disk to GPT and boot in UEFI. You can convert without data loss using mbr2gpt, or, if you do not need the data, delete the partitions in setup so it recreates the correct layout. Choosing the right USB boot entry (UEFI vs legacy) is often all it takes.
What this error means
A disk is laid out as either GPT or MBR, and the firmware boots as either UEFI or legacy BIOS. The two are paired: UEFI goes with GPT, legacy goes with MBR. Setup enforces this, so a mismatch between how you booted the installer and how the target disk is partitioned stops the install.
Modern systems, and Windows 11 in particular, want UEFI with GPT. So the cleanest fix is to get the disk onto GPT and boot the installer in UEFI mode. If the disk has data you need, mbr2gpt converts it in place; if not, letting setup delete and recreate the partitions produces the correct layout automatically.
Common causes
The installer booted in UEFI mode but the disk is MBR.
The installer booted in legacy mode but the disk is GPT.
The USB was booted from the wrong boot menu entry.
Windows 11 needs UEFI and GPT, but the disk is MBR.
CSM or legacy support is enabled in firmware.
Expert insight
“This one is just a pairing problem: UEFI wants GPT, legacy wants MBR, and setup will not mix them. Half the time the disk is fine and you simply booted the USB from the wrong entry, the legacy one instead of the UEFI one, so I fix it at the boot menu. For Windows 11 I want UEFI and GPT, so if the disk is MBR I convert it with mbr2gpt without losing data, or if it is a clean install I just delete the partitions in setup and let it build the right layout.”
2Then set the firmware to UEFI. Back up first; choose the correct disk number.
Method 4
Wipe and recreate the layout (clean install)
1If you do not need the data, in setup delete all partitions on the target disk.
2With the installer booted in UEFI, setup recreates a correct GPT layout automatically.
3Continue the install.
Method 5
Convert with diskpart (clean install only)
1Alternatively, at the setup prompt run diskpart, select the disk, and convert (this erases the disk):
diskpart
list disk
select disk 0
clean
convert gpt
exit
2Only do this on a disk whose data you do not need.
This is a UEFI-with-GPT versus legacy-with-MBR mismatch. Often you just booted the USB from the wrong entry, so pick the UEFI boot entry. For Windows 11 you want UEFI and GPT, so convert an MBR disk with mbr2gpt to keep data, or delete the partitions in setup for a clean install to get the right layout automatically.
Frequently asked questions
What does the selected disk is of the GPT partition style mean?
It means you booted Windows setup in legacy BIOS mode but the target disk is GPT, which only works with UEFI. The MBR variant is the opposite mismatch. Match the boot mode to the disk.
How do I fix it quickly?
At the boot menu, pick the UEFI entry for your USB so it matches a GPT disk. Booting the right mode often clears the error without any conversion.
How do I convert MBR to GPT without losing data?
Run mbr2gpt /validate /disk:0 then mbr2gpt /convert /disk:0 from the setup command prompt or within Windows, then set the firmware to UEFI. Back up first and use the correct disk number.
What does Windows 11 require?
Windows 11 requires UEFI firmware with a GPT disk. If your disk is MBR, convert it to GPT and boot in UEFI mode, or the install will be blocked.
Can I just wipe the disk?
Yes, on a clean install where you do not need the data. Delete all partitions in setup while booted in UEFI, and setup recreates the correct GPT layout automatically.
Why is CSM involved?
CSM (legacy support) makes the firmware boot in BIOS mode, which pairs with MBR. For UEFI and GPT, disable CSM so the installer boots in UEFI mode.
Still not working?
If converting and matching the boot mode still fails, the disk may have a mix of partition types or a protective MBR issue. On a clean install, fully clean the disk with diskpart and let setup rebuild it; for a data disk, verify the mbr2gpt validation output for what blocked the conversion. You can also submit your error to us for a tailored fix.
