Level: Intermediate
Estimated Time: 15–20 minutes
Operating System: Windows 11 (UEFI systems)
Summary
After replacing a Linux installation (such as Pop!_OS, Ubuntu, or Arch Linux) with Windows 11, old boot entries may remain visible in UEFI firmware.
This happens because UEFI boot configuration is stored in:
- EFI System Partition (ESP)
- UEFI NVRAM boot entries
Both must be cleaned.
⚠️ Before you start: Backup your data. Modifying the EFI partition or NVRAM entries can make your system unbootable if done incorrectly.
Technical Background
EFI System Partition (ESP)
The EFI System Partition (ESP) is a FAT32-formatted partition that stores the bootloaders for all installed operating systems. On Windows systems, it typically ranges from 100–500 MB in size and is labeled as "System".
Typical structure:
EFI/
├── Microsoft/
├── Boot/
├── pop_os/
├── systemd/
├── ubuntu/
└── linux/
⚠️ Do NOT remove:
NVRAM Boot Entries
UEFI firmware stores boot entries in non-volatile memory.
Each entry contains:
- GUID identifier
- Description
- Path to EFI loader
- Device reference
Removing EFI files does not remove NVRAM entries.
Step 1 — Mount EFI Partition
Open Command Prompt as Administrator.
diskpart
list disk
select disk 0
list partition
⚠️ Replace 0 with your system disk number.
select partition 1
assign letter=Z
exit
⚠️ Replace 1 with the EFI partition (~100–500 MB, Type: System)
Step 2 — Remove Linux Bootloader Files
Z:
cd \EFI
dir
Remove Linux folders:
rmdir /s /q systemd
rmdir /s /q pop_os
Parameters:
/s → removes directories recursively/q → quiet mode (no confirmation)
Permission Errors
takeown /f systemd /r /d y
Parameters:
/f → target folder/r → recursive/d y → auto confirm
On Portuguese Windows, use /d s instead of /d y.
icacls systemd /grant Administrators:F /t
rmdir /s /q systemd
Step 3 — Remove NVRAM Boot Entries
3.1 List firmware entries
bcdedit /enum firmware
Example output:
Firmware Application (101fffff)
-------------------------------
identifier {29c75bf6-3303-11f1-b7f4-e7fe7d8485ec}
device partition=\Device\HarddiskVolume1
path \EFI\systemd\systemd-bootx64.efi
description Pop!_OS
Firmware Application (101fffff)
-------------------------------
identifier {bootmgr}
device partition=\Device\HarddiskVolume2
path \EFI\Microsoft\Boot\bootmgfw.efi
description Windows Boot Manager
3.2 Identify entries to remove
Remove entries that reference:
- systemd
- pop_os
- ubuntu
- linux
3.3 Delete orphan entry
bcdedit /delete {29c75bf6-3303-11f1-b7f4-e7fe7d8485ec} /f
Parameter:
/f → force deletion without confirmation
⚠️ NEVER delete:
Step 4 — Remove drive letter
diskpart
select disk 0
select partition 1
remove letter=Z
exit
Troubleshooting
Problem 1 — Access denied
takeown /f systemd /r /d y
icacls systemd /grant Administrators:F /t
rmdir /s /q systemd
Problem 2 — delete fails
Possible causes:
- entry already removed
- firmware protected entry
- invalid reference
Solution:
- reboot
- remove EFI files first
- run again
Problem 3 — entry still appears
Possible causes:
- firmware cache
- fallback recreated
- BIOS bug
Solutions:
- reboot twice
- load BIOS defaults
- update BIOS
Problem 4 — Windows does not boot
Method 1 — Startup Repair
- Boot Windows installer USB
- Repair your computer
- Startup Repair
Method 2 — Recovery Command Prompt
bcdboot C:\Windows /s Z: /f UEFI
Commands Used
Version Notes
| Version | Date | Changes |
|---|
| 1.0 | April 2026 | Initial procedure |
| 1.1 | April 2026 | Added EFI explanation |
| 1.2 | April 2026 | Added NVRAM cleanup |
| 1.3 | April 2026 | Added troubleshooting |
| 1.4 | April 2026 | Added command table |
| 1.5 | April 2026 | Added recovery section |
| 1.6 | April 2026 | Safety and locale improvements |
✅ Quick Checklist (click to expand)
- [ ] Backup completed
- [ ] Disk/Partition numbers verified
- [ ] Microsoft/ and Boot/ preserved
- [ ] {bootmgr} and {current} not deleted
- [ ] Drive letter removed
Tested Environment
- Windows 11 24H2
- UEFI firmware
- GPT disk
- Pop!_OS systemd-boot
Disclaimer
Backup before modifying EFI partition.
Verify disk and partition numbers carefully.
