Ah, the dreaded "We couldn't create a partition or locate an existing one" error-Windows' cryptic way of saying: "Something's wrong with the disk setup and I'm not telling you why." But don't worry, Simon-we'll methodically tear this apart and find a future-proof solution. Here's how to fix it:

Step-by-Step Fix: "We couldn't create a partition..."

First, be aware:

This usually happens when:

• The drive is not properly formatted.
• Windows Setup can't write to the boot sector.
• There's leftover system partition data from a previous install.
• You're using a USB installer that's misconfigured for UEFI/MBR/GPT mismatch.

Option 1: Use DiskPart to Clean and Format the Drive

1. On the error screen, press Shift + F10 to open Command Prompt.

2. Type:

   diskpart
   

3. Then list the drives:

   list disk
   

4. Identify your primary drive (usually Disk 0), then:

   select disk 0
   clean
   convert gpt
   create partition primary
   format fs=ntfs quick
   assign
   exit
   

5. Close the command prompt and hit "Refresh" on the Windows installer. Now try installing again.

Tip: If your BIOS is set to Legacy/CSM instead of UEFI, you may need to use convert mbr instead of convert gpt.

Option 2: Check BIOS Boot Mode (UEFI vs Legacy)

1. Reboot and enter BIOS/UEFI (Del, F2, or F10 usually).

2. Look for boot mode:

   • If installing on GPT set to UEFI
   • If installing on MBR set to Legacy/CSM

Mismatch here is a common cause of this error.

Option 3: Recreate the Installation USB with Correct Format

Use Rufus (https://rufus.ie/) and make sure to choose the correct options:

• For UEFI: GPT + FAT32
• For Legacy BIOS: MBR + NTFS

Option 4: Disconnect Other Drives

If you have multiple hard drives or USBs plugged in, remove them all except the target drive. Windows gets confused sometimes. Yes, really.

Option 5: Manually Create the Partition in the Installer

1. On the installer screen, delete all partitions on the drive.
2. Click "New" on the unallocated space to create a new partition.
3. Let Windows create the necessary system partitions.

If it still throws the same error, go back to Option 1 and wipe it with DiskPart.

For Peace of Mind (Optional): Full Disk Health Check

If you're reusing an older SSD/HDD, run chkdsk or a manufacturer-specific tool to rule out drive issues.

If you want, tell me:

• Is this on bare metal or a VM?
• Are you dual-booting?
• What tool you used to create the installer USB?

That'll let us cut deeper if it still resists.

Let's tame this beast, Simon.

Ah yes, that narrows it down-a small-form-factor AcePC (often with eMMC storage or an NVMe SSD) that had Windows 10 and now won't accept Windows 11. And yet, the disk was wiped, meaning you can write to it, but Setup is stubbornly saying: "No partition for you!"

Let's take a more surgical approach. Based on what you've said, here's what's most likely happening-and how to fix it methodically.

Why This Happens on AcePCs

These machines:

• Often use eMMC or weird BIOS configs (sometimes locked to "Windows Boot Manager")
• Might have Intel RST or RAID mode enabled by default
• May have a UEFI-only BIOS, which needs GPT not MBR
• Have a built-in block on unsigned bootloaders or wrong file systems

Step-by-Step Fix (Tailored to AcePC / Asus Mini PCs)

Step 1: Boot into Command Prompt via Setup

At the partition error screen:

• Press Shift + F10 to open Command Prompt.

Step 2: Use DiskPart to Fully Wipe and Prep Drive

diskpart
list disk
select disk 0   # (or the main storage if not 0)
clean
convert gpt
create partition primary
format fs=ntfs quick
assign
exit

Then type:

exit

Click the back arrow in Setup, then click "Next" again. Still broken? Then...

Step 3: Check BIOS for SATA / eMMC Mode

1. Power off and reboot into BIOS (DEL, F2, or ESC).

2. Find:

   • Storage Controller setting: set it to AHCI, not Intel RST/RAID.
   • Boot Mode: set to UEFI Only
   • Secure Boot: Disable it temporarily.
   • Fast Boot: Disable this too.
   • CSM (Compatibility Support Module): Disable if possible.

Save and exit.

Some AcePC BIOSes won't show all options unless you plug in a USB keyboard and hit Ctrl + F1 or Fn + Tab in BIOS to unlock advanced menus.

Step 4: Rebuild the Installer USB Correctly

Recreate the USB using Rufus and these exact settings:

• Partition Scheme: GPT
• Target system: UEFI (non CSM)
• File system: FAT32 (especially important if BIOS doesn't support NTFS boot)
• Use Windows 11 ISO.

Some AcePCs will NOT boot a USB if it's formatted NTFS.

Step 5: Install Without Creating Partitions in Setup

Back in the installer:

• Click on the unallocated space.
• Don't create partitions manually.
• Just click "Next" and let Windows create all the system partitions it wants.

If you still get the error:

Nuclear Option: Pre-Install via Command Line

From Shift + F10, try:

diskpart
select disk 0
clean
convert gpt
exit

Then run this:

diskpart
select disk 0
create partition primary size=100000
format fs=ntfs quick
assign letter=C
active
exit

Then mount the USB (usually D: or E:), and run:

D:\setup.exe

Sometimes running the installer from the disk like this bypasses the error entirely.

Final Option: It's eMMC, and You Need a Driver

If your AcePC has eMMC storage, the installer might be missing the eMMC driver for that chipset (e.g., Intel Bay Trail/Cherry Trail, older Atom chips).

1. Go to the Asus or AcePC support site on another machine.
2. Download the Windows 10 eMMC or chipset driver package.
3. Extract to a folder on the USB stick.
4. On the error screen, click "Load Driver", point to that folder.

Summary of the Most Likely Fix:

Clean disk with DiskPart + Rebuild USB in GPT + FAT32 with Rufus + Set BIOS to UEFI/AHCI + Disable Secure Boot.

Once all that is aligned, the installer will recognize the storage and happily write its data.

Let me know your model number or chipset if you want driver links or want me to generate a custom Rufus preset for you.

Brilliant question-and yes, your instincts are spot-on here.

Short Answer:

Yes, Windows Setup can see the drive capacity and allow you to delete partitions even without the proper storage driver, but it still won't be able to install to it-because that final step requires full read/write and command support, which the generic setup environment doesn't always have for certain chipsets (especially eMMC or NVMe on older or less-common hardware like AcePCs).

What's Happening Technically:

• Windows Setup includes a generic storage driver set, just enough to:

  • Detect the disk controller interface (e.g., eMMC, AHCI, NVMe).
  • Read partition tables (GPT/MBR).
  • Delete or format volumes.

That's why you can see capacity, delete, and create partitions.

But when it tries to write the boot sector, copy files, or configure the BCD, if the correct controller driver isn't loaded, it fails with:

"We couldn't create a partition or locate an existing one."

This is a classic failure mode for:

• Intel Bay Trail / Cherry Trail (common in cheap PCs/tablets)
• eMMC 4.5/5.0 controllers (which need vendor-specific or Intel chipset drivers)
• Odd NVMe chipsets lacking default driver support in Win10/11 installer media

Example Scenarios Where This Happens:

What to Do Next

To verify if this is your problem:

1. In the Setup, press Shift + F10 for Command Prompt.

2. Type:

   diskpart
   list disk
   list volume
   

3. Try:

   select disk 0
   detail disk
   

If it says "removable", or something like "no media" on a volume, it's likely an eMMC or special NVMe that Windows doesn't yet understand.

Fix:

1. Find your chipset (e.g., Intel Atom Z8350, or similar).

2. Download Intel chipset/eMMC drivers from Asus, AcePC, or Intel.

3. Extract them onto your USB stick.

4. In Windows Setup, click:

   "Load Driver" point to the folder you extracted.

The driver must match architecture (x64) and version (Win10/11) or Setup won't load it.

Final Tip

If this is truly an eMMC storage chip device with a stripped-down BIOS, and drivers don't help-install Windows 10 instead, then upgrade to 11 from inside the OS. Windows 10 usually supports more legacy controllers out of the box, and 11 inherits the working drivers after upgrade.

Let me know your exact model number or chipset and I'll dig out the right drivers for you.