[Batch/PowerShell] Master Offline Windows OS Servicing & Multi-EFI Bootloader Repair Toolkit

Ramesh Sharma · Aug 15, 2026

[Batch/PowerShell] Master Offline Windows OS Servicing & Multi-EFI Bootloader Repair Toolkit

Hello everyone,

I wanted to share a native batch and PowerShell offline maintenance and bootloader servicing toolkit that I developed and refined for managing complex Windows environments (multi-boot configurations, Windows To Go, cloned drives, and live WinPE rescue environments like Sergei Strelec).

Unlike heavy third-party GUI utilities, this toolkit relies entirely on native Windows command-line binaries (DISM, BCDBoot, BCDEdit, Robocopy, and PowerShell Partition cmdlets) without injecting stale NVRAM firmware entries or risking GPT/EFI partition corruption.

Key Features

Multi-OS Hardware Bus Detection: Automatically scans all mounted volumes to identify Windows installations, distinguishing between internal fixed disks, external USB drives, and Windows To Go (WTG).
Interactive Manual EFI Mounting: Scans hardware for physical EFI System Partitions (ESP), displays current unused/available drive letters, and allows you to map specific letters without collisions.
One-Click EFI Cleanup: Unmounts active or all mounted EFI partitions cleanly via partition access paths without breaking volume metadata.
Non-Destructive EFI & BCD Backup: Mirrors the active EFI structure and exports a pure BCD registry hive snapshot directly to the selected target OS drive (\EFI_Backup\).
Safe BCD & EFI Restore: Restores boot files and imports the BCD database without requiring full partition formatting.
Offline DISM & Servicing: Inspect image editions, execute offline /ScanHealth, run read-only CHKDSK, or spawn target-rooted command shells instantly.
WinPE & Live OS Agnostic: Fully compatible with running Windows 11/10 installations as well as WinPE recovery media.

Setup Instructions

Create a dedicated folder on your drive or WinPE USB (e.g., C:\DETECTION OF WINDOWS).
Inside that folder, create two files: Detect-Windows.cmd and Master-Servicing.cmd.
Paste the respective code blocks below into each file.
Important: Save both files using ANSI encoding in Notepad.
Right-click Master-Servicing.cmd and select Run as administrator (or execute directly in WinPE).

Code 1: Detect-Windows.cmd

Code:

@echo off
setlocal enabledelayedexpansion

:: ====================================================
:: Windows Installed Drive & EFI Partition Detector
:: ====================================================

echo ====================================================
echo        Windows Installed Drive Detector
echo ====================================================
echo.

set "OS_COUNT=0"
set "EFI_COUNT=0"
set "DETECTED_OS_DRIVES="
set "DETECTED_EFI_DRIVES="

:: ----------------------------------------------------
:: 1. Detect Installed Windows OS Partitions
:: ----------------------------------------------------
echo --- WINDOWS OS INSTALLATIONS ---

powershell -NoProfile -ExecutionPolicy Bypass -Command ^
  "$drives = Get-PSDrive -PSProvider FileSystem | Where-Object { Test-Path ($_.Root + 'Windows\System32\ntoskrnl.exe') }; " ^
  "foreach ($d in $drives) { " ^
  "  $letter = $d.Name + ':'; " ^
  "  $regPath = $letter + '\Windows\System32\config\SOFTWARE'; " ^
  "  $prodName = 'Windows OS'; " ^
  "  $build = ''; $displayVer = ''; " ^
  "  if (Test-Path $regPath) { " ^
  "    reg load HKLM\OFFLINE_TEMP $regPath >$null 2>&1; " ^
  "    if ($?) { " ^
  "      $prodName = (Get-ItemProperty -Path 'HKLM:\OFFLINE_TEMP\Microsoft\Windows NT\CurrentVersion' -Name ProductName -ErrorAction SilentlyContinue).ProductName; " ^
  "      $build = (Get-ItemProperty -Path 'HKLM:\OFFLINE_TEMP\Microsoft\Windows NT\CurrentVersion' -Name CurrentBuild -ErrorAction SilentlyContinue).CurrentBuild; " ^
  "      $displayVer = (Get-ItemProperty -Path 'HKLM:\OFFLINE_TEMP\Microsoft\Windows NT\CurrentVersion' -Name DisplayVersion -ErrorAction SilentlyContinue).DisplayVersion; " ^
  "      [GC]::Collect(); [GC]::WaitForPendingFinalizers(); " ^
  "      reg unload HKLM\OFFLINE_TEMP >$null 2>&1; " ^
  "    } " ^
  "  } " ^
  "  $part = Get-Partition -DriveLetter $d.Name -ErrorAction SilentlyContinue; " ^
  "  $disk = if ($part) { Get-Disk -Number $part.DiskNumber -ErrorAction SilentlyContinue } else { $null }; " ^
  "  $busType = if ($disk) { $disk.BusType.ToString() } else { 'Unknown' }; " ^
  "  $wtg = 'Standard Installation'; " ^
  "  if (Test-Path ($letter + '\Windows\System32\wlanpref.netxml')) { $wtg = 'Standard Installation' }; " ^
  "  if ($busType -eq 'USB') { $wtg = 'Windows To Go (WTG)' }; " ^
  "  Write-Host ('[FOUND OS] Drive ' + $letter); " ^
  "  if ($build) { Write-Host ('  - Edition:      ' + $prodName + ' [Build ' + $build + ', Version ' + $displayVer + ']') } else { Write-Host ('  - Edition:      ' + $prodName) }; " ^
  "  Write-Host ('  - Hardware Bus: ' + (if ($busType -eq 'USB') { 'External USB Drive' } else { 'Internal Fixed Disk' })); " ^
  "  Write-Host ('  - OS Type:      ' + $wtg); " ^
  "  Write-Host '----------------------------------------------------'; " ^
  "}"

:: Export list of OS drive letters
for /f "tokens=*" %%A in ('powershell -NoProfile -ExecutionPolicy Bypass -Command "$d = Get-PSDrive -PSProvider FileSystem | Where-Object { Test-Path ($_.Root + 'Windows\System32\ntoskrnl.exe') }; ($d.Name) -join ' '"') do (
    set "DETECTED_OS_DRIVES=%%A"
)

:: Count detected OS partitions
for %%D in (%DETECTED_OS_DRIVES%) do (
    set /a OS_COUNT+=1
)
echo Total OS installations detected: %OS_COUNT%
echo.

:: ----------------------------------------------------
:: 2. Detect Mounted EFI System Partitions (ESP)
:: ----------------------------------------------------
echo --- EFI SYSTEM PARTITIONS (ESP) ---

powershell -NoProfile -ExecutionPolicy Bypass -Command ^
  "$efis = Get-PSDrive -PSProvider FileSystem | Where-Object { Test-Path ($_.Root + 'EFI\Microsoft\Boot\bootmgfw.efi') }; " ^
  "foreach ($e in $efis) { " ^
  "  $eLetter = $e.Name + ':'; " ^
  "  Write-Host ('[FOUND EFI] Drive ' + $eLetter + ' (Mounted)'); " ^
  "  Write-Host ('  - Boot File Path: ' + $eLetter + '\EFI\Microsoft\Boot\bootmgfw.efi'); " ^
  "  Write-Host '----------------------------------------------------'; " ^
  "}"

:: Export list of EFI drive letters
for /f "tokens=*" %%B in ('powershell -NoProfile -ExecutionPolicy Bypass -Command "$e = Get-PSDrive -PSProvider FileSystem | Where-Object { Test-Path ($_.Root + 'EFI\Microsoft\Boot\bootmgfw.efi') }; ($e.Name) -join ' '"') do (
    set "DETECTED_EFI_DRIVES=%%B"
)

:: Count detected EFI partitions
for %%E in (%DETECTED_EFI_DRIVES%) do (
    set /a EFI_COUNT+=1
)
echo Total mounted EFI partitions detected: %EFI_COUNT%
echo.

:: ----------------------------------------------------
:: 3. Interactive Target Selection & Export
:: ----------------------------------------------------
echo ====================================================
echo Select Target OS Drive to Export
echo ====================================================
echo Available OS Drives:  %DETECTED_OS_DRIVES%

:: Set first detected drive as default
for %%F in (%DETECTED_OS_DRIVES%) do (
    if not defined DEFAULT_TARGET set "DEFAULT_TARGET=%%F:"
)
if not defined DEFAULT_TARGET set "DEFAULT_TARGET=C:"

echo Default selection: %DEFAULT_TARGET%
echo.
set "USER_OS_CHOICE="
set /p "USER_OS_CHOICE=Enter Target OS Drive Letter (or press Enter for default %DEFAULT_TARGET%): "

if "%USER_OS_CHOICE%"=="" set "USER_OS_CHOICE=%DEFAULT_TARGET%"
set "USER_OS_CHOICE=%USER_OS_CHOICE:~0,1%:"

:: Match or assign active EFI Drive
set "ACTIVE_EFI=Unassigned"
for %%E in (%DETECTED_EFI_DRIVES%) do (
    if not defined FIRST_EFI set "FIRST_EFI=%%E:"
)
if defined FIRST_EFI set "ACTIVE_EFI=%FIRST_EFI%"

:: Pass environment variables back to caller
endlocal & (
    set "TARGET_OS_DRIVE=%USER_OS_CHOICE%"
    set "EFI_DRIVE=%ACTIVE_EFI%"
)
exit /b 0

Code 2: Master-Servicing.cmd

Code:

@echo off
setlocal enabledelayedexpansion

:RESTART_SERVICER
cls
echo Launching Windows Detection Engine...
echo.

if not exist "%~dp0Detect-Windows.cmd" (
    echo [ERROR] Detect-Windows.cmd was not found in: %~dp0
    pause
    exit /b 1
)

:: Call the detection script
call "%~dp0Detect-Windows.cmd"

if not defined TARGET_OS_DRIVE (
    echo.
    echo [ERROR] No target OS drive was selected or detected.
    pause
    exit /b 1
)

:MENU
cls
echo ====================================================
echo             MASTER OFFLINE OS SERVICER              
echo ====================================================
echo   Active Target OS Drive : [%TARGET_OS_DRIVE%]
echo   Active EFI Drive       : [%EFI_DRIVE%]
echo ====================================================
echo.
echo Select an action:
echo.
echo   [1] Display DISM Target OS Information
echo   [2] Run DISM Health Check (ScanHealth)
echo   [3] List Users and System Directories
echo   [4] Run Read-Only CHKDSK File System Check
echo   [5] Open Command Prompt pointed at %TARGET_OS_DRIVE%
echo   [6] Rescan / Change Target Drive
echo   [7] Backup EFI and BCD Store for %TARGET_OS_DRIVE%
echo   [8] Restore EFI and BCD Store for %TARGET_OS_DRIVE%
echo   [9] Manual Mount EFI Partition
echo  [10] Auto-Unmount All Mounted EFI Partitions
echo  [11] Fix / Rebuild Bootloader on %EFI_DRIVE% for %TARGET_OS_DRIVE%
echo  [12] Unmount Selected EFI Drive [%EFI_DRIVE%]
echo   [0] Exit
echo.
echo ====================================================
set "CHOICE="
set /p "CHOICE=Enter choice (0-12): "

if "%CHOICE%"=="1" goto DISM_INFO
if "%CHOICE%"=="2" goto DISM_SCAN
if "%CHOICE%"=="3" goto LIST_FILES
if "%CHOICE%"=="4" goto CHKDSK_CHECK
if "%CHOICE%"=="5" goto OPEN_CMD
if "%CHOICE%"=="6" goto RESTART_SERVICER
if "%CHOICE%"=="7" goto BACKUP_EFI
if "%CHOICE%"=="8" goto RESTORE_EFI
if "%CHOICE%"=="9" goto MOUNT_ALL_EFI
if "%CHOICE%"=="10" goto UNMOUNT_ALL_EFI
if "%CHOICE%"=="11" goto REBUILD_BCD
if "%CHOICE%"=="12" goto UNMOUNT_TARGET_EFI
if "%CHOICE%"=="0" exit /b 0

echo Invalid choice. Please enter a number between 0 and 12.
timeout /t 2 >nul
goto MENU

:: ======================================================
:: SUBROUTINES
:: ======================================================

:DISM_INFO
cls
echo ====================================================
echo Querying DISM Image Information on %TARGET_OS_DRIVE%
echo ====================================================
echo.
dism /Image:%TARGET_OS_DRIVE%\ /Get-CurrentEdition
echo.
pause
goto MENU

:DISM_SCAN
cls
echo ====================================================
echo Running DISM ScanHealth on %TARGET_OS_DRIVE%
echo ====================================================
echo.
dism /Image:%TARGET_OS_DRIVE%\ /Cleanup-Image /ScanHealth
echo.
pause
goto MENU

:LIST_FILES
cls
echo ====================================================
echo Directories on %TARGET_OS_DRIVE%
echo ====================================================
echo.
echo Users Directory:
dir "%TARGET_OS_DRIVE%\Users" /b 2>nul
echo.
echo System32 Key Executables:
dir "%TARGET_OS_DRIVE%\Windows\System32\ntoskrnl.exe" 2>nul
echo.
pause
goto MENU

:CHKDSK_CHECK
cls
echo ====================================================
echo Running Read-Only CHKDSK on %TARGET_OS_DRIVE%
echo ====================================================
echo.
chkdsk %TARGET_OS_DRIVE%
echo.
pause
goto MENU

:OPEN_CMD
cls
echo Opening Command Prompt targeting %TARGET_OS_DRIVE%...
echo Type 'exit' to return to the Master Menu.
echo.
cmd /k "cd /d %TARGET_OS_DRIVE%\"
goto MENU

:BACKUP_EFI
cls
echo ====================================================
echo            EFI AND BCD BACKUP UTILITY
echo ====================================================
echo.
echo   Target OS Drive : [%TARGET_OS_DRIVE%]
echo   Target EFI Drive: [%EFI_DRIVE%]
echo ====================================================
echo.

if not defined EFI_DRIVE (
    echo [ERROR] No mounted EFI partition was selected.
    pause
    goto MENU
)
if /i "%EFI_DRIVE%"=="Unassigned" (
    echo [ERROR] Target EFI partition is Unassigned.
    pause
    goto MENU
)

echo [1/4] Exporting BCD store snapshot...
bcdedit /export "%TARGET_OS_DRIVE%\BCD_Backup.bcd"

echo [2/4] Creating backup folder structure...
mkdir "%TARGET_OS_DRIVE%\EFI_Backup\EFI\Microsoft\Boot" 2>nul

echo [3/4] Mirroring EFI files from %EFI_DRIVE%\EFI...
robocopy "%EFI_DRIVE%\EFI" "%TARGET_OS_DRIVE%\EFI_Backup\EFI" /E /ZB /XF BCD* /R:0 /W:0

echo [4/4] Finalizing BCD file placement...
copy /y "%TARGET_OS_DRIVE%\BCD_Backup.bcd" "%TARGET_OS_DRIVE%\EFI_Backup\EFI\Microsoft\Boot\BCD"
del /f /q "%TARGET_OS_DRIVE%\BCD_Backup.bcd" 2>nul

echo.
echo ====================================================
echo   EFI Backup Completed Successfully on %TARGET_OS_DRIVE%
echo ====================================================
echo.
pause
goto MENU

:RESTORE_EFI
cls
echo ====================================================
echo            EFI AND BCD RESTORE UTILITY
echo ====================================================
echo.
echo   Target OS Drive : [%TARGET_OS_DRIVE%]
echo   Target EFI Drive: [%EFI_DRIVE%]
echo ====================================================
echo.

if not defined TARGET_OS_DRIVE (
    echo [ERROR] No Target OS Drive is defined. Please run Option 6 first.
    echo.
    pause
    goto MENU
)

if not defined EFI_DRIVE goto NO_EFI_TARGET
if /i "%EFI_DRIVE%"=="Unassigned" goto NO_EFI_TARGET
goto VERIFY_BACKUP

:NO_EFI_TARGET
echo [ERROR] Target EFI Drive is Unassigned or not mounted.
echo Please run Option 9 to mount, then Option 6 to select it.
echo.
pause
goto MENU

:VERIFY_BACKUP
if not exist "%TARGET_OS_DRIVE%\EFI_Backup\EFI\Microsoft\Boot\BCD" (
    echo [ERROR] No valid EFI backup found in %TARGET_OS_DRIVE%\EFI_Backup\
    echo Please run Option 7 to create a backup before attempting a restore.
    echo.
    pause
    goto MENU
)

if not exist "%EFI_DRIVE%\" (
    echo [ERROR] Target EFI partition [%EFI_DRIVE%] is not accessible.
    echo.
    pause
    goto MENU
)

echo WARNING: This will restore EFI boot files to %EFI_DRIVE%
echo from backup folder: %TARGET_OS_DRIVE%\EFI_Backup\
echo.
set "CONFIRM_RESTORE="
set /p "CONFIRM_RESTORE=Proceed with restore? (Y/N): "
if /i not "%CONFIRM_RESTORE%"=="Y" goto MENU

echo.
echo [1/3] Restoring EFI files to %EFI_DRIVE%\EFI...
robocopy "%TARGET_OS_DRIVE%\EFI_Backup\EFI" "%EFI_DRIVE%\EFI" /E /ZB /XF BCD* /R:1 /W:1

echo.
echo [2/3] Restoring BCD store...
copy /y "%TARGET_OS_DRIVE%\EFI_Backup\EFI\Microsoft\Boot\BCD" "%EFI_DRIVE%\EFI\Microsoft\Boot\BCD"

echo.
echo [3/3] Validating BCD store...
bcdedit /store "%EFI_DRIVE%\EFI\Microsoft\Boot\BCD" /enum active >nul 2>&1

if %errorlevel% equ 0 (
    echo.
    echo ====================================================
    echo   [SUCCESS] EFI and BCD Restored Successfully on %EFI_DRIVE%
    echo ====================================================
) else (
    echo.
    echo [WARNING] BCD copied, but validation returned an alert.
)

echo.
pause
goto MENU

:MOUNT_ALL_EFI
cls
echo ====================================================
echo         MANUAL EFI PARTITION MOUNT UTILITY
echo ====================================================
echo.

:MOUNT_LOOP
echo Available (Unused) Drive Letters:
powershell -NoProfile -ExecutionPolicy Bypass -Command "$used = (Get-PSDrive -PSProvider FileSystem).Name; $avail = [char[]](68..90) | Where-Object { $used -notcontains [string]$_ }; Write-Host ' ' ($avail -join ' ') -ForegroundColor Cyan"
echo.

echo Detected EFI System Partitions on Hardware:
echo ----------------------------------------------------
powershell -NoProfile -ExecutionPolicy Bypass -Command "Get-Partition | Where-Object { $_.GptType -eq '{c12a7328-f81f-11d2-ba4b-00a0c93ec93b}' } | ForEach-Object { $letter = if ($_.DriveLetter) { [string]$_.DriveLetter + ':' } else { 'Hidden (Unassigned)' }; Write-Host (' Disk ' + $_.DiskNumber + ' | Partition ' + $_.PartitionNumber + ' | Size: ' + [math]::Round($_.Size/1MB) + ' MB | Current Letter: ' + $letter) -ForegroundColor Yellow; }"
echo ----------------------------------------------------
echo.

set "TARGET_DISK="
set /p "TARGET_DISK=Enter Disk Number to mount (or 'M' to return to Main Menu): "
if /i "%TARGET_DISK%"=="M" goto MENU
if "%TARGET_DISK%"=="" goto MENU

set "TARGET_PART="
set /p "TARGET_PART=Enter Partition Number for that Disk: "
if "%TARGET_PART%"=="" goto MENU

set "CHOSEN_LETTER="
set /p "CHOSEN_LETTER=Enter Drive Letter to assign (e.g. D or H): "
if "%CHOSEN_LETTER%"=="" goto MENU

set "CHOSEN_LETTER=%CHOSEN_LETTER:~0,1%"

echo.
echo Assigning letter %CHOSEN_LETTER%: to Disk %TARGET_DISK% Partition %TARGET_PART%...
powershell -NoProfile -ExecutionPolicy Bypass -Command "Set-Partition -DiskNumber %TARGET_DISK% -PartitionNumber %TARGET_PART% -NewDriveLetter '%CHOSEN_LETTER%' -ErrorAction SilentlyContinue"

if %errorlevel% equ 0 (
    echo.
    echo [SUCCESS] Mounted Disk %TARGET_DISK% Partition %TARGET_PART% as %CHOSEN_LETTER%:
) else (
    echo.
    echo [ERROR] Failed to mount. Please verify disk and partition numbers.
)

echo.
echo ----------------------------------------------------
set "ANOTHER="
set /p "ANOTHER=Do you want to mount another EFI partition? (Y/N): "
if /i "%ANOTHER%"=="Y" (
    cls
    echo ====================================================
    echo         MANUAL EFI PARTITION MOUNT UTILITY
    echo ====================================================
    echo.
    goto MOUNT_LOOP
)
goto MENU

:UNMOUNT_ALL_EFI
cls
echo ====================================================
echo        AUTO-UNMOUNT ALL MOUNTED EFI PARTITIONS
echo ====================================================
echo.
echo Removing assigned letters from all EFI System Partitions...
echo.

powershell -NoProfile -ExecutionPolicy Bypass -Command "Get-Partition | Where-Object { $_.GptType -eq '{c12a7328-f81f-11d2-ba4b-00a0c93ec93b}' -and $_.DriveLetter } | ForEach-Object { Write-Host 'Removing drive letter' ($_.DriveLetter + ':') 'from Disk' $_.DiskNumber 'Partition' $_.PartitionNumber; $_ | Remove-PartitionAccessPath -AccessPath ($_.DriveLetter + ':\') -ErrorAction SilentlyContinue; }"

echo.
echo All EFI drive letters have been removed cleanly.
echo.
pause
goto MENU

:REBUILD_BCD
cls
echo ====================================================
echo             REBUILD EFI BOOTLOADER
echo ====================================================
echo.
echo   Target OS Drive : [%TARGET_OS_DRIVE%]
echo   Target EFI Drive: [%EFI_DRIVE%]
echo.

if not defined EFI_DRIVE (
    echo [ERROR] No EFI Drive variable is set.
    pause
    goto MENU
)
if /i "%EFI_DRIVE%"=="Unassigned" (
    echo [ERROR] Target EFI partition is Unassigned.
    pause
    goto MENU
)

bcdboot %TARGET_OS_DRIVE%\Windows /s %EFI_DRIVE% /f UEFI /v

if %errorlevel% equ 0 (
    echo.
    echo ====================================================
    echo   Bootloader successfully rebuilt on %EFI_DRIVE%!
    echo ====================================================
) else (
    echo.
    echo [ERROR] Failed to rebuild bootloader. Verify drive letters.
)
echo.
pause
goto MENU

:UNMOUNT_TARGET_EFI
cls
echo ====================================================
echo       UNMOUNT SELECTED EFI DRIVE [%EFI_DRIVE%]
echo ====================================================
echo.

if not defined EFI_DRIVE (
    echo [ERROR] No active EFI drive letter is defined.
    pause
    goto MENU
)
if /i "%EFI_DRIVE%"=="Unassigned" (
    echo [ERROR] Target EFI partition is already unassigned.
    pause
    goto MENU
)

set "CLEAN_LETTER=%EFI_DRIVE:~0,1%"
echo Removing drive letter assignment for %CLEAN_LETTER%: ...
echo.

powershell -NoProfile -ExecutionPolicy Bypass -Command "Get-Partition | Where-Object { $_.AccessPaths -contains '%CLEAN_LETTER%:\' } | Remove-PartitionAccessPath -AccessPath '%CLEAN_LETTER%:\'" >nul 2>&1

set "EFI_DRIVE=Unassigned"
echo Letter %CLEAN_LETTER%: unassigned successfully.
echo.
pause
goto MENU

Standard Workflow

Run Master-Servicing.cmd as Administrator.
The detection script lists all Windows builds along with mounted EFI partitions across your drives.
Select your desired Target OS Drive (e.g., C: or K:).
If your EFI partition is not yet mounted, choose Option [9] to mount it to an available drive letter (e.g., D: or H:).
Choose Option [7] to create an EFI and BCD backup directly on the target OS drive.
Service your image or repair your bootloader safely with Option [11].
When finished, unmount the EFI partitions using Option [10] or Option [12] to return your system to its clean, hidden-ESP state.

courtesy :--- Detect Windows Drives Without Diskpart - Google Gemini

Ramesh Sharma · Aug 16, 2026

Update / Patch for Detect-Windows.cmd

An inline expression in PowerShell 5.1 caused a minor syntax error when displaying the Hardware Bus type. Below is the updated and fully tested version of Detect-Windows.cmd.

Code:

@echo off
setlocal enabledelayedexpansion

:: ====================================================
:: Windows Installed Drive & EFI Partition Detector
:: ====================================================

echo ====================================================
echo        Windows Installed Drive Detector
echo ====================================================
echo.

set "OS_COUNT=0"
set "EFI_COUNT=0"
set "DETECTED_OS_DRIVES="
set "DETECTED_EFI_DRIVES="

:: ----------------------------------------------------
:: 1. Detect Installed Windows OS Partitions
:: ----------------------------------------------------
echo --- WINDOWS OS INSTALLATIONS ---

powershell -NoProfile -ExecutionPolicy Bypass -Command ^
  "$drives = Get-PSDrive -PSProvider FileSystem | Where-Object { Test-Path ($_.Root + 'Windows\System32\ntoskrnl.exe') }; " ^
  "foreach ($d in $drives) { " ^
  "  $letter = $d.Name + ':'; " ^
  "  $regPath = $letter + '\Windows\System32\config\SOFTWARE'; " ^
  "  $prodName = 'Windows OS'; " ^
  "  $build = ''; $displayVer = ''; " ^
  "  if (Test-Path $regPath) { " ^
  "    reg load HKLM\OFFLINE_TEMP $regPath >$null 2>&1; " ^
  "    if ($?) { " ^
  "      $prodName = (Get-ItemProperty -Path 'HKLM:\OFFLINE_TEMP\Microsoft\Windows NT\CurrentVersion' -Name ProductName -ErrorAction SilentlyContinue).ProductName; " ^
  "      $build = (Get-ItemProperty -Path 'HKLM:\OFFLINE_TEMP\Microsoft\Windows NT\CurrentVersion' -Name CurrentBuild -ErrorAction SilentlyContinue).CurrentBuild; " ^
  "      $displayVer = (Get-ItemProperty -Path 'HKLM:\OFFLINE_TEMP\Microsoft\Windows NT\CurrentVersion' -Name DisplayVersion -ErrorAction SilentlyContinue).DisplayVersion; " ^
  "      [GC]::Collect(); [GC]::WaitForPendingFinalizers(); " ^
  "      reg unload HKLM\OFFLINE_TEMP >$null 2>&1; " ^
  "    } " ^
  "  } " ^
  "  $part = Get-Partition -DriveLetter $d.Name -ErrorAction SilentlyContinue; " ^
  "  $disk = if ($part) { Get-Disk -Number $part.DiskNumber -ErrorAction SilentlyContinue } else { $null }; " ^
  "  $busType = if ($disk) { $disk.BusType.ToString() } else { 'Unknown' }; " ^
  "  $busDesc = if ($busType -eq 'USB') { 'External USB Drive' } else { 'Internal Fixed Disk' }; " ^
  "  $wtg = 'Standard Installation'; " ^
  "  if (Test-Path ($letter + '\Windows\System32\wlanpref.netxml')) { $wtg = 'Standard Installation' }; " ^
  "  if ($busType -eq 'USB') { $wtg = 'Windows To Go (WTG)' }; " ^
  "  Write-Host ('[FOUND OS] Drive ' + $letter); " ^
  "  if ($build) { Write-Host ('  - Edition:      ' + $prodName + ' [Build ' + $build + ', Version ' + $displayVer + ']') } else { Write-Host ('  - Edition:      ' + $prodName) }; " ^
  "  Write-Host ('  - Hardware Bus: ' + $busDesc); " ^
  "  Write-Host ('  - OS Type:      ' + $wtg); " ^
  "  Write-Host '----------------------------------------------------'; " ^
  "}"

:: Export list of OS drive letters
for /f "tokens=*" %%A in ('powershell -NoProfile -ExecutionPolicy Bypass -Command "$d = Get-PSDrive -PSProvider FileSystem | Where-Object { Test-Path ($_.Root + 'Windows\System32\ntoskrnl.exe') }; ($d.Name) -join ' '"') do (
    set "DETECTED_OS_DRIVES=%%A"
)

:: Count detected OS partitions
for %%D in (%DETECTED_OS_DRIVES%) do (
    set /a OS_COUNT+=1
)
echo Total OS installations detected: %OS_COUNT%
echo.

:: ----------------------------------------------------
:: 2. Detect Mounted EFI System Partitions (ESP)
:: ----------------------------------------------------
echo --- EFI SYSTEM PARTITIONS (ESP) ---

powershell -NoProfile -ExecutionPolicy Bypass -Command ^
  "$efis = Get-PSDrive -PSProvider FileSystem | Where-Object { Test-Path ($_.Root + 'EFI\Microsoft\Boot\bootmgfw.efi') }; " ^
  "foreach ($e in $efis) { " ^
  "  $eLetter = $e.Name + ':'; " ^
  "  Write-Host ('[FOUND EFI] Drive ' + $eLetter + ' (Mounted)'); " ^
  "  Write-Host ('  - Boot File Path: ' + $eLetter + '\EFI\Microsoft\Boot\bootmgfw.efi'); " ^
  "  Write-Host '----------------------------------------------------'; " ^
  "}"

:: Export list of EFI drive letters
for /f "tokens=*" %%B in ('powershell -NoProfile -ExecutionPolicy Bypass -Command "$e = Get-PSDrive -PSProvider FileSystem | Where-Object { Test-Path ($_.Root + 'EFI\Microsoft\Boot\bootmgfw.efi') }; ($e.Name) -join ' '"') do (
    set "DETECTED_EFI_DRIVES=%%B"
)

:: Count detected EFI partitions
for %%E in (%DETECTED_EFI_DRIVES%) do (
    set /a EFI_COUNT+=1
)
echo Total mounted EFI partitions detected: %EFI_COUNT%
echo.

:: ----------------------------------------------------
:: 3. Interactive Target Selection & Export
:: ----------------------------------------------------
echo ====================================================
echo Select Target OS Drive to Export
echo ====================================================
echo Available OS Drives:  %DETECTED_OS_DRIVES%

:: Set first detected drive as default
for %%F in (%DETECTED_OS_DRIVES%) do (
    if not defined DEFAULT_TARGET set "DEFAULT_TARGET=%%F:"
)
if not defined DEFAULT_TARGET set "DEFAULT_TARGET=C:"

echo Default selection: %DEFAULT_TARGET%
echo.
set "USER_OS_CHOICE="
set /p "USER_OS_CHOICE=Enter Target OS Drive Letter (or press Enter for default %DEFAULT_TARGET%): "

if "%USER_OS_CHOICE%"=="" set "USER_OS_CHOICE=%DEFAULT_TARGET%"
set "USER_OS_CHOICE=%USER_OS_CHOICE:~0,1%:"

:: Match or assign active EFI Drive
set "ACTIVE_EFI=Unassigned"
for %%E in (%DETECTED_EFI_DRIVES%) do (
    if not defined FIRST_EFI set "FIRST_EFI=%%E:"
)
if defined FIRST_EFI set "ACTIVE_EFI=%FIRST_EFI%"

:: Pass environment variables back to caller
endlocal & (
    set "TARGET_OS_DRIVE=%USER_OS_CHOICE%"
    set "EFI_DRIVE=%ACTIVE_EFI%"
)
exit /b 0

Ramesh Sharma · Aug 16, 2026

Please use zip folder DETECTION OF WINDOWS.7z attached herewith to find both cmd files Master-Servicing.cmd and Detect-Windows.cmd .These files are updated and patched and are working 100% correctly without any error. Option 1 now detects image versions of both online and offline hardware bus.
Thank you very much for watching this thread and sharing your valuable time.

Ramesh Sharma · Wednesday at 1:18 AM

Follow up
Hello everyone,
1. I have run Master-Servicing.cmd from Windows 11 bootable media. Please see the workflow in the images attatched herewith.
2. I made some changes in a loop in Master-Servicing.cmd and Detect-Windows.cmd with the guidelines from Gemini AI to run it without any dependencies. So please download the zip folder DETECTION OF WINDOWS.7z latest, attatched herewith.
3. The finalized, tested archive DETECTION OF WINDOWS.7z is attached below containing:
Detect-Windows.cmd
Master-Servicing.cmd
Works seamlessly across standard Windows 10/11 Desktop, official Windows Setup media (Shift + F10), Sergei Strelec PE, and custom Windows
ADK WinPE environments.
4. I have attatched pdf file of whole conversation with Gemini AI .
5. I repaired the corrupt EFI bootloader on WTG using these files in folder DETECTION OF WINDOWS.7z
6. Download , extract compressed folder to Windows 11 boot drive's FAT32 partition. Boot from this drive, at language settings screen press Shift+F10 and run following command from x:\sources>
7. x:\sources>wmic logicaldisk get caption,volumename
8. Type usb drive letter. In my case it is I:
9. I:\>cd DETECTION OF WINDOWS
10. I:\DETECTION OF WINDOWS>Master-Servicing.cmd
11. Now you can use all options from 1 to 12 without any errror.

Thank you very much.

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[Batch/PowerShell] Master Offline Windows OS Servicing & Multi-EFI Bootloader Repair Toolkit

Ramesh Sharma

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Ramesh Sharma

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[Batch/PowerShell] Master Offline Windows OS Servicing & Multi-EFI Bootloader Repair Toolkit

Ramesh Sharma

Well-known member

Attachments

My Computer My Computer

At a glance

Ramesh Sharma

Well-known member

Attachments

My Computer My Computer

At a glance

Ramesh Sharma

Well-known member

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My Computer My Computer

At a glance

Ramesh Sharma

Well-known member

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My Computer My Computer

At a glance

Latest Support Threads

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My Computer

My Computer

My Computer

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