‘We Couldn’t Create a New Partition’: Fix the Install Error in 3 Steps

The 3-step fix (the opinionated version)

Step 1: Confirm the boot mode and disk style are compatible

Most “couldn’t create a new partition” failures are not about “space.” They’re about the installer trying to create boot-critical partitions (EFI System Partition for UEFI, System Reserved for BIOS/Legacy) and failing because the machine booted in the wrong mode for the current disk layout, or vice versa.

Do this: decide whether you are installing in UEFI + GPT (recommended for anything remotely modern) or Legacy BIOS + MBR (only if you have a hard requirement). Then make the firmware boot mode match, and make the disk style match.

• UEFI booted installer? Disk should be GPT and have an EFI System Partition (ESP) created by Setup.
• Legacy/CSM booted installer? Disk should be MBR; Setup will create System Reserved and active partition logic.

Step 2: Make the target disk boring again (clean partition table and metadata)

Installers fail when disks aren’t “empty” in the ways the installer cares about. You can have free space and still have stale RAID metadata, leftover Linux LVM signatures, broken GPT headers, or recovery partitions that block the layout Windows wants.

Do this: if the disk can be wiped, wipe it properly (partition table + metadata). If it can’t be wiped, make a surgical change: free contiguous unallocated space and ensure there’s room for ESP/MSR/recovery.

Step 3: Eliminate the “wrong disk” and “missing driver” traps

This error also appears when Setup is attempting to place boot partitions on a different disk than the one you selected (often because multiple disks are present, or because the USB stick is confusing the “Disk 0” ordering). It also appears when the disk is visible but not writable in a sane way because the controller driver is missing (common with some VMD/RAID modes on newer platforms).

Do this: temporarily disconnect other drives, use a USB 2.0 port if the installer is weird, and if you’re in RAID/VMD mode, provide the correct storage controller driver or switch to AHCI if your environment allows it.

Dry-funny but true: Windows Setup is like a very polite bouncer. It won’t explain the dress code, it’ll just deny entry.

Fast diagnosis playbook

If you only have five minutes before someone escalates you to “person who breaks the laptop in half,” use this order. It finds the bottleneck faster than poking randomly at partitions.

First: Are we booted in UEFI or Legacy?

• Check the installer boot entry in firmware boot menu. If you see two entries for the USB (one says “UEFI: …”), pick the one you intend.
• Why it matters: UEFI expects GPT and an EFI System Partition. Legacy expects MBR. Mismatch causes Setup to fail when creating system partitions.

Second: Is the disk actually writable and clean?

• Open command prompt (Shift+F10) and use DiskPart to list disks, check for read-only, and inspect partition style.
• Why it matters: stale metadata, read-only attributes, or corrupted partition tables often show up as “can’t create partition.”

Third: Are we accidentally installing with multiple disks present?

• Unplug all other drives (including extra internal SATA/NVMe if possible). Leave only the target disk and the installer USB.
• Why it matters: Setup may put the boot partition on Disk 0 and the OS on Disk 1. If Disk 0 is removable, weird, or has no space, you get this error.

If those pass: suspect drivers and controller mode

• If NVMe isn’t visible, or disk shows but behaves oddly, load the storage driver in Setup or change firmware storage mode (VMD/RAID → AHCI) if acceptable.

What the error actually means (and what it doesn’t)

The phrasing is misleading. Setup isn’t just trying to create “a partition.” It’s trying to create the right partitions in the right order on the right disk with the right firmware assumptions.

What’s happening under the hood

Windows Setup typically wants to create:

• EFI System Partition (ESP) (UEFI installs): FAT32, typically 100–300 MB. Holds bootloaders.
• Microsoft Reserved Partition (MSR) (GPT installs): small, hidden, used for GPT housekeeping.
• Primary OS partition (NTFS): the big one.
• Recovery partition: used for WinRE; size varies by version.

If any of those can’t be created—no contiguous space at the right boundary, wrong disk style, conflicting existing partitions, read-only disk, or inability to write GPT/MBR structures—Setup throws the “couldn’t create/locate” error and stops.

What it is not

• It’s not always a failing drive. Don’t RMA hardware just because Setup got grumpy.
• It’s not always “not enough space.” Plenty of failures happen on completely empty disks.
• It’s not fixed by running Setup again and hoping harder (though I’ve seen teams try).

One useful mental model: treat this as a boot chain provisioning failure, not a “partition management” failure. Your job is to make boot mode, disk layout, and disk identity agree.

Interesting facts and a little history

• MBR dates back to the early 1980s era of IBM PC compatibility. It’s tiny, simple, and carries a lot of legacy baggage.
• GPT was designed as part of EFI/UEFI to replace MBR’s limits, including the classic 2 TB barrier (with 512-byte sectors) and four-primary-partition ceiling.
• UEFI boot typically requires an EFI System Partition formatted as FAT32, not NTFS—because firmware implementations commonly understand FAT well enough to load boot files.
• Windows Setup often chooses where to place boot partitions based on disk enumeration order, not your emotional attachment to “Disk 0.” Multiple disks can derail this.
• Some RAID/VMD modes hide NVMe drives behind a controller that needs a driver in Windows Setup; Linux installers often “just see it,” which creates false confidence.
• “Dynamic disks” were Microsoft’s attempt at flexible volume management before Storage Spaces became the modern answer; they complicate installs and aren’t worth it for most endpoints.
• Partition alignment matters (especially for SSDs and 4K-sector disks). Modern tools align by default, but mixed tooling can create odd boundaries that confuse or hurt performance.
• Stale metadata survives formatting (RAID headers, LVM signatures). “Delete partition” is not the same as “disk is clean.”

Hands-on tasks: commands, outputs, and decisions (12+)

All tasks assume you’re inside Windows Setup. When you see the partition screen, press Shift+F10 to open a command prompt. These are the moves that actually change outcomes.

Task 1: List disks and confirm which one is the target

cr0x@server:~$ diskpart
Microsoft DiskPart version 10.0.22621.1

DISKPART> list disk

  Disk ###  Status         Size     Free     Dyn  Gpt
  --------  -------------  -------  -------  ---  ---
  Disk 0    Online          476 GB      0 B
  Disk 1    Online           28 GB    28 GB

What it means: Disk 1 is likely your USB installer (28 GB). Disk 0 is the internal SSD (476 GB). If you accidentally select Disk 1 later, you’ll have a bad time.

Decision: Proceed with Disk 0. If you see multiple internal disks, unplug the non-target ones before continuing.

Task 2: Show disk details and check if it’s read-only

cr0x@server:~$ diskpart
DISKPART> select disk 0

Disk 0 is now the selected disk.

DISKPART> detail disk

Samsung SSD 970 EVO Plus 500GB
Disk ID: {A1B2C3D4-E5F6-...}
Type   : NVMe
Status : Online
Read-only  : No
Boot Disk  : No
Pagefile Disk  : No
Hibernation File Disk  : No
Crashdump Disk  : No
Clustered Disk  : No

What it means: If Read-only : Yes, Setup may fail to create partitions.

Decision: If read-only, clear attributes (next task). If it’s not online, bring it online.

Task 3: Clear read-only attributes (disk and volume)

cr0x@server:~$ diskpart
DISKPART> select disk 0

DISKPART> attributes disk

Current Read-only State : Yes
Read-only  : Yes
Boot Disk  : No

DISKPART> attributes disk clear readonly

Disk attributes cleared successfully.

DISKPART> attributes disk

Current Read-only State : No
Read-only  : No

What it means: Some OEM images or previous tools can mark a disk read-only. Clearing it allows partition writes.

Decision: Retry installation. If it flips back to read-only, suspect firmware-level security, failing media, or a storage controller issue.

Task 4: Check partition style (GPT vs MBR)

cr0x@server:~$ diskpart
DISKPART> list disk

  Disk ###  Status         Size     Free     Dyn  Gpt
  --------  -------------  -------  -------  ---  ---
  Disk 0    Online          476 GB    128 MB        *

What it means: The * under Gpt indicates GPT. If it’s blank, it’s MBR.

Decision: If you intend UEFI, prefer GPT. If you are booted in Legacy mode and it’s GPT, either change firmware boot to UEFI or convert disk to MBR (not recommended unless required).

Task 5: Identify existing partitions that may block Setup

cr0x@server:~$ diskpart
DISKPART> select disk 0

DISKPART> list partition

  Partition ###  Type              Size     Offset
  -------------  ----------------  -------  -------
  Partition 1    Recovery           990 MB  1024 KB
  Partition 2    System             100 MB  991 MB
  Partition 3    Reserved            16 MB  1091 MB
  Partition 4    Primary            475 GB  1107 MB

What it means: This disk already has a prior Windows layout. Setup should typically be able to reuse it, but corruption, mismatch boot mode, or an undersized recovery partition can still cause failures.

Decision: If you’re doing a clean install, deleting partitions from the UI (or wiping via DiskPart) is safer than trying to surgically preserve a broken layout.

Task 6: The clean-slate option (destructive): clean + convert gpt

cr0x@server:~$ diskpart
DISKPART> select disk 0

DISKPART> clean

DiskPart succeeded in cleaning the disk.

DISKPART> convert gpt

DiskPart successfully converted the selected disk to GPT format.

DISKPART> exit

What it means: clean removes partition information. It does not securely erase every sector, but it makes the disk “blank” for Setup’s purposes. convert gpt sets the disk style.

Decision: After this, return to Setup and click “Refresh.” Select the unallocated space and click “Next.” If you need data preserved, do not do this.

Joke #1: DiskPart clean is like deleting a calendar: your meetings are gone, but the building still exists.

Task 7: If you must keep data: shrink from within Windows (not Setup)

Windows Setup is a terrible place to attempt “careful.” If you need to keep an existing Windows volume and make room, boot into Windows (or WinPE) and shrink properly. In Setup, you can delete partitions, but resizing often gets messy.

cr0x@server:~$ diskpart
DISKPART> list volume

  Volume ###  Ltr  Label        Fs     Type        Size     Status     Info
  ----------  ---  -----------  -----  ----------  -------  ---------  --------
  Volume 0     C   OS           NTFS   Partition    450 GB  Healthy    Boot
  Volume 1         Recovery     NTFS   Partition    990 MB  Healthy    Hidden

DISKPART> select volume 0

DISKPART> shrink desired=102400

DiskPart successfully shrunk the volume by: 100 GB

What it means: You created 100 GB of unallocated space. Setup can install into that unallocated space if boot partitions can be created and firmware mode matches.

Decision: If shrink fails with “not enough space,” you need to consolidate immovable files, or accept a wipe.

Task 8: Verify the installer USB isn’t being treated as the primary disk

cr0x@server:~$ diskpart
DISKPART> list disk

  Disk ###  Status         Size     Free     Dyn  Gpt
  --------  -------------  -------  -------  ---  ---
  Disk 0    Online           28 GB      0 B
  Disk 1    Online          476 GB    476 GB        *

What it means: Disk ordering flipped: your USB is Disk 0. Setup sometimes tries to place boot files on Disk 0, which is a removable drive and not what you want.

Decision: Use a different USB port, remove other removable storage, or physically disconnect non-target disks. If possible, boot installer from a port/controller that enumerates after internal storage.

Task 9: Force creation of a correct UEFI boot layout (manual partitions)

If Setup refuses to automatically build partitions, you can create them yourself. This is especially useful after cleaning the disk, or when you want deterministic sizes.

cr0x@server:~$ diskpart
DISKPART> select disk 0

DISKPART> clean

DiskPart succeeded in cleaning the disk.

DISKPART> convert gpt

DiskPart successfully converted the selected disk to GPT format.

DISKPART> create partition efi size=260

DiskPart succeeded in creating the specified partition.

DISKPART> format quick fs=fat32 label="SYSTEM"

  100 percent completed

DiskPart successfully formatted the volume.

DISKPART> create partition msr size=16

DiskPart succeeded in creating the specified partition.

DISKPART> create partition primary

DiskPart succeeded in creating the specified partition.

DISKPART> format quick fs=ntfs label="Windows"

  100 percent completed

DiskPart successfully formatted the volume.

DISKPART> assign letter=W

DiskPart successfully assigned the drive letter or mount point.

DISKPART> exit

What it means: You built a standard GPT layout with an ESP and MSR, then an NTFS primary partition.

Decision: Back in Setup, choose the “Windows” partition and continue. If Setup still can’t proceed, suspect boot mode mismatch (you may have booted Legacy) or a driver/controller issue.

Task 10: Check for and remove stale storage metadata (wipe first/last sectors)

Sometimes clean isn’t enough because some installers/drivers trip over metadata at the end of the disk (old RAID signatures, etc.). clean all is slow but thorough: it writes zeros across the disk.

cr0x@server:~$ diskpart
DISKPART> select disk 0

DISKPART> clean all

DiskPart is cleaning the disk...

What it means: This can take a long time on large disks. But it removes hidden leftovers that can confuse setup or RAID firmware.

Decision: Use this when you suspect leftover metadata or corruption and you can afford the time. If you’re on a tight window, try normal clean first.

Task 11: Inspect logs for Setup’s real complaint

When the UI says “couldn’t create,” the logs usually say “couldn’t write boot code,” “couldn’t format ESP,” or “no suitable system partition.” Look at Setup logs in the temporary install environment.

cr0x@server:~$ notepad X:\Windows\Panther\setupact.log

What it means: Notepad opens the log. Search for Error, SP (system partition), EFI, 0x codes, and “partition.”

Decision: If you see errors about writing to disk, suspect read-only state, driver, or failing hardware. If you see “no EFI system partition,” suspect UEFI/GPT mismatch or missing ESP.

Task 12: Confirm the disk is visible with the expected controller driver

If the disk is missing entirely, you’re not “partitioning wrong.” You’re missing a driver or the controller is in a mode Setup doesn’t support out of the box.

cr0x@server:~$ wmic diskdrive get model,interfacetype,size,status
Model                                 InterfaceType  Size           Status
Samsung SSD 970 EVO Plus 500GB         NVMe           500105249280   OK

What it means: If nothing shows up, Setup doesn’t see the drive through its current driver stack.

Decision: Load the correct storage driver from removable media in Setup (“Load driver”), or change firmware storage mode (e.g., RAID/VMD to AHCI) if your organization’s standard build allows it.

Task 13: Rebuild boot files after manual partitioning (advanced)

If you laid down partitions and applied an image, or you’re repairing after a failed attempt, you may need to explicitly create boot entries.

cr0x@server:~$ bcdboot W:\Windows /s S: /f UEFI
Boot files successfully created.

What it means: bcdboot copies boot files to the ESP mounted as S: and configures UEFI boot entries.

Decision: Use when the OS partition exists but the machine won’t boot or Setup can’t “locate an existing one.” If it errors, your ESP may not be FAT32, not mounted, or you may not be in UEFI mode.

Task 14: Check current boot mode from WinPE/Setup environment

cr0x@server:~$ reg query HKLM\System\CurrentControlSet\Control /v PEFirmwareType
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control
    PEFirmwareType    REG_DWORD    0x2

What it means: 0x2 typically indicates UEFI; 0x1 indicates BIOS/Legacy.

Decision: If you intended UEFI but it’s BIOS, reboot and pick the “UEFI:” boot entry for the installer USB, and ensure CSM/Legacy is disabled.

Task 15: Detect 4K sector disks and alignment-sensitive platforms

cr0x@server:~$ wmic diskdrive get model,bytespersector
Model                                 BytesPerSector
Samsung SSD 970 EVO Plus 500GB         512

What it means: Some devices report 4096 bytes/sector (native 4K). It should still work, but older tooling or odd firmware can cause partitioning issues.

Decision: If you see 4096 and you’re using an ancient installer image, update the install media. Don’t fight geometry with 2012-era ISOs.

Joke #2: If your install media is older than your interns, don’t be surprised when it can’t find an NVMe drive.

Common mistakes: symptom → root cause → fix

1) Symptom: Disk shows “Unallocated space,” but Setup still can’t create partitions

Root cause: Boot mode mismatch (UEFI vs Legacy) or disk is MBR while installer is in UEFI mode (or vice versa).

Fix: Confirm boot mode (Task 14), then clean + convert gpt for UEFI (Task 6), or switch firmware to match the disk style.

2) Symptom: Error appears only when multiple disks are attached

Root cause: Setup tries to place system partition on Disk 0, but you selected Disk 1 for the OS. Disk 0 might be the USB, or a small SSD with no space, or a drive you don’t intend to touch.

Fix: Disconnect non-target drives. Ensure internal target disk is the only fixed disk. Re-run Setup.

3) Symptom: Disk is visible, but partition creation fails instantly

Root cause: Disk is read-only, write-protected by policy, or has controller/firmware issues causing write failures.

Fix: Check attributes (Task 3). If it persists, check firmware security settings and controller mode; consider hardware diagnostics.

4) Symptom: NVMe drive doesn’t appear in Setup at all

Root cause: Storage controller driver missing (common with RAID/VMD configurations), or the platform is in a RAID mode Windows Setup can’t handle without drivers.

Fix: Load the driver during Setup or switch to AHCI if allowed. Confirm visibility (Task 12).

5) Symptom: “Windows cannot be installed to this disk” plus partition error

Root cause: You’re trying to install UEFI Windows to an MBR disk, or Legacy Windows to a GPT disk.

Fix: Convert disk (Task 6) or reboot and change boot mode. Don’t mix-and-match.

6) Symptom: Setup works on some machines, fails on “identical” ones

Root cause: Firmware defaults differ (CSM on/off, VMD enabled), or disk enumeration differs due to port order and USB controller behavior.

Fix: Standardize firmware settings. Use the same boot entry choice (UEFI). Keep only one target disk attached.

7) Symptom: You can create partitions in DiskPart, but Setup still refuses

Root cause: The partitions you created don’t match the boot mode (e.g., created ESP but booted Legacy), or the installer is attempting to create recovery/system partitions and can’t due to sizing or offset constraints.

Fix: Re-check firmware type (Task 14). Let Setup create partitions automatically after clean when possible.

8) Symptom: Setup keeps selecting the wrong partition for system files

Root cause: Existing ESP from an old disk layout, or multiple ESPs across disks. Windows will happily pick one; you may not like which one.

Fix: Disconnect other disks. Wipe the target disk’s old ESP (destructive). Ensure only one ESP exists during install.

Checklists / step-by-step plan (safe and fast)

Plan A: You can wipe the disk (recommended)

1. Disconnect all other internal and external drives except the installer USB and the target disk.
2. Boot the installer in UEFI mode (choose the “UEFI:” entry in firmware boot menu).
3. On the partition screen, press Shift+F10.
4. Run DiskPart to identify the target disk:
   • Task 1 + Task 2
5. Wipe and set GPT:
   • Task 6 (clean + convert gpt)
6. Exit DiskPart, “Refresh,” select unallocated space, click “Next.”
7. If it fails again:
   • Confirm boot mode (Task 14)
   • Inspect logs (Task 11)
   • Suspect controller driver (Task 12)

Plan B: You must preserve data (be honest about risk)

1. Stop trying to do delicate surgery in Windows Setup. Boot into the existing OS or a proper WinPE environment.
2. Back up what matters (yes, even if you’re “just shrinking”).
3. Shrink the existing OS volume to create unallocated space (Task 7).
4. Reboot installer in the correct boot mode (UEFI preferred).
5. Ensure there is an ESP on the same disk that will hold Windows (or let Setup create it if space allows).
6. If multi-disk: disconnect non-target disks so Setup can’t get creative.

Plan C: The disk isn’t visible (driver/controller problem)

1. Check if the disk appears in wmic diskdrive (Task 12).
2. If not, reboot into firmware:
   • Check storage mode: AHCI vs RAID/VMD.
   • If organization allows, switch to AHCI for standard Windows installs.
3. Alternatively, keep RAID/VMD and use “Load driver” in Setup with the correct controller driver package.
4. After the disk appears, return to Plan A.

Plan D: Setup is confused by disk order (the “Disk 0 is the USB” problem)

1. Remove extra USB devices (other sticks, external drives, card readers).
2. Move the installer USB to a different port (often a different controller). Prefer a plain USB port over a hub.
3. Reboot and try again; re-check disk ordering (Task 8).
4. If still wrong: consider using a different installer media or writing the USB again (bad USBs create weird partial failures).

Three mini-stories from corporate life (names changed, pain preserved)

Mini-story 1: The incident caused by a wrong assumption

They were rolling out a new laptop model to a few hundred staff. Imaging was “standard”: boot USB, install, let the task sequence do the rest. Halfway through the first batch, technicians started reporting the same error: “We couldn’t create a new partition.” The assumption was immediate and confident: “These SSDs are defective.”

A well-meaning manager escalated to procurement, who started drafting an RMA plan. Meanwhile, the floor techs tried the classic rituals: reseat the SSD, swap USB sticks, try again. Intermittent success made everyone more convinced it was hardware, because nothing says “hardware problem” like inconsistent results, right?

It turned out to be firmware configuration drift. Some units shipped with “UEFI Only,” others with CSM/Legacy enabled by default. The imaging USB had two boot entries and techs were selecting whichever appeared first. Same media, different boot mode, different expectations. When you booted Legacy, Setup wanted MBR behavior; the disk had GPT from manufacturing. Partition creation failed where Setup tried to establish the system partition.

The fix was dull: enforce UEFI-only in firmware, train techs to always pick the “UEFI:” boot entry, and wipe/convert disk to GPT during the task sequence. The RMA plan quietly died, procurement returned to their natural habitat, and everyone pretended it was obvious all along.

Mini-story 2: The optimization that backfired

A different shop had a clever idea: keep a small “tools” SSD installed in every workstation to speed up deployments and collect logs. The tools disk was always Disk 0, and the target OS disk was Disk 1. In their lab, it worked fine—because their imaging process explicitly handled boot partition placement.

Then they introduced a new Windows build and changed the install flow slightly. They stopped doing explicit partition creation and let Windows Setup “figure it out,” because it usually does. Setup did what Setup does: it tried to put system partitions on Disk 0, because Disk 0 is special in its own head.

Except Disk 0 was the tools SSD and it was nearly full. Setup couldn’t create the required system partition and threw the “couldn’t create a new partition” error, even though Disk 1 had hundreds of gigabytes free. The team spent hours debating “why Setup is broken” rather than asking “why Setup is touching the wrong disk.”

The rollback was immediate: unplug the tools disk during install, or better, change the process to explicitly partition the target disk and ensure boot files land there. The optimization (a permanent extra disk) wasn’t wrong, but it violated a silent assumption in Windows Setup: disk enumeration order matters, and it will not ask permission.

Mini-story 3: The boring but correct practice that saved the day

A financial services team had a habit that looked like paranoia: they maintained a one-page “build contract” for every hardware platform. It listed firmware settings (UEFI-only, Secure Boot policy, storage mode), minimum installer version, and a canonical partition scheme. The doc was not glamorous. It was, however, obeyed.

One day a new motherboard revision arrived mid-quarter. Same model name, slightly different firmware defaults. A junior tech started getting partition creation failures during OS install. Instead of improvising, they followed the contract: verify boot mode, verify storage controller mode, verify disk visibility, then wipe and install.

The contract forced a crucial step: confirm firmware boot mode via a known check (Task 14 equivalent) rather than trusting the boot menu label. They found the unit had silently enabled CSM. Flip it back to UEFI-only, reinstall, done.

No incident, no drama, no “we need a new golden image.” Just a boring checklist working exactly as intended. Reliability is often just paperwork with teeth.

Operations quote (paraphrased idea): Gene Kranz’s reliability mindset: focus on discipline and preparation—failures are managed by procedure, not improvisation.

FAQ

1) Does this error always mean the drive is failing?

No. It often means boot mode mismatch, a confused disk order, or missing storage controller drivers. Check read-only state and logs before blaming hardware.

2) Should I use GPT or MBR?

Use GPT unless you have a hard requirement for Legacy BIOS. UEFI + GPT is the modern default and avoids MBR limitations.

3) I converted to GPT but still get the error. Now what?

Confirm you actually booted the installer in UEFI mode (Task 14). If you’re in BIOS mode with a GPT disk, Setup will fight you. Also check multi-disk scenarios and controller drivers.

4) Is it safe to run DiskPart clean?

It’s safe for the disk, unsafe for your data. It removes partition information and makes volumes inaccessible. Do it only when you intend to wipe the disk.

5) What’s the difference between clean and clean all?

clean removes partition metadata quickly. clean all writes zeros across the disk and takes much longer, but is more thorough when stale metadata is suspected.

6) Why does unplugging other drives help?

Because Setup may create boot partitions on a different disk than the OS partition, usually based on enumeration order. Fewer disks means fewer surprises.

7) Can I fix this without reinstalling?

If the OS files are already laid down but it won’t boot, sometimes yes: rebuilding the EFI boot files with bcdboot can help (Task 13). If Setup cannot create partitions at all, you typically need to adjust disk/boot mode first.

8) The disk doesn’t show up in Setup, but it shows in BIOS. Why?

Firmware can see devices that the Windows installer cannot without the right driver (common with RAID/VMD). Load the storage controller driver or switch to AHCI if permitted.

9) What about Secure Boot—does it cause this partition error?

Secure Boot usually affects booting unsigned media, not partition creation. But firmware settings come in bundles; toggling Secure Boot sometimes flips UEFI/CSM behavior. Verify boot mode explicitly.

10) Can a weird USB stick cause the error?

Yes, indirectly. Some systems enumerate the USB as Disk 0 and Setup gets confused about where to place boot partitions. Also, flaky media can cause partial read failures that look like storage problems.

Practical next steps

If you remember nothing else: make boot mode, disk style, and disk identity agree. This error is rarely solved by random clicking and often solved by one deliberate reset.

1. Pick UEFI + GPT unless you have a real reason not to. Then boot the installer in UEFI mode and convert the disk to GPT.
2. Wipe the disk properly when you can: DiskPart clean and reinstall. If you can’t wipe, stop and plan the data-preserving path outside Setup.
3. Remove ambiguity: disconnect other disks, reduce USB clutter, and don’t let Setup decide where boot files go across multiple drives.
4. When it still fails, read the logs and check controller drivers. The UI is vague; the logs are blunt.

Do these in order and you’ll turn “We couldn’t create a new partition” from a time-sink into a speed bump. The rest is just keeping your coffee away from the keyboard—reliability starts with physical layer best practices.