Clear previous Windows installations

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Works with Windows 10 and 11Works with Windows Vista, XP, 7, 8, 10, 11, and Windows Server 2008 or newer.

• Windows onlyThis script improves your privacy on Windows
• Single actionThis page belongs to a script, containing basic changes to achieve a task.
• Impact: High

  System Functionality / Data Loss Risk: High

  This action improves privacy with high impact when you run the recommended script.

• Batch (batchfile)These changes use Windows system commands to update your settings.
• Administrator rights requiredThis script requires privilege access to do the system changes
• Fully reversible

  You can fully restore this action (revert back to the original behavior) using this website.

  The restore/revert methods provided here can help you fix issues.

Overview

Missing Good Quality Documentation

This page does not yet meet PrivacyLearn's documentation standards. The script/action is stable and verified by community. Here are some options for you to understand its functionality:

Computer-generated docs ^(PREVIEW)

This documentation may be low quality but still useful.

Read computer-generated explanation

This documentation is automatically extracted from the code implementation.

This publication: clear previous Windows installations — simplifies the details surrounding how to avoid data collection that risks privacy enforcement on Windows.

Encouraging creativity and innovation is a core advantage of privacy protection. Ready for better sensitive data privacy protection controls? Now, follow the guide to make the recommended adjustment. Set aside enough time to work through the guide without feeling rushed. A calm approach will make the process much smoother.

References

• 7 Application Security Best Practices
• The Difference between Data Security and Privacy
• Application permissions (Wikipedia)

Technical Details

While this file system, this playbook modifies your system to benefit from data leakage prevention to be able to enhance important privacy guardrail. This tweak helps improved disk performance to help help apps respond more quickly. This change orchestrates security parameters to help minimize digital data handling risks and this would to realize controlled security perimeter. It helps use system resources more efficiently, to accomplish efficient threat prevention.

Explore similar guides

Gives more context about the goal of the changes

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Review code

Requires technical knowledge about Batch (batchfile)

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Edit this page to improve

Requires technical knowledge about YAML and Git

Edit this page

Not Advised

This script should only be used by advanced users.

This script is not recommended for daily use as it breaks important functionality.

Consider creating a system restore point before doing any changes.

Apply Now

Choose one of three ways to apply:

Download script

Download and run the script directly

• No app needed
• Offline usage
• Easy-to-apply
• Free
• Open-source

Apply protection

Help

How to apply or restore "Clear previous Windows installations" using script

• ≈ 2 min to complete
• Tools: Web Browser
• Difficulty: Simple
• ≈ 5 instructions

1. 1

   Download

   Download the script file by clicking on the   Apply protection  button above.
   Use   Undo protection button above to restore changes.
2. 2

   Keep the file

   If warned by your browser, keep the file.
3. 3

   Open

   Open the downloaded file.
4. 4

   Exit

   Once it's done, press any key to exit the window.
5. 5

   Restart

   Restart your computer for all changes to take effect.

Apply with privacy.sexy

Guided, automated application with safety checks

• Recommended for most users
• Includes safety checks
• Free
• Open-source
• Popular
• Offline/Online usage

Open privacy.sexy

Help

How to apply or restore "Clear previous Windows installations" using privacy.sexy

• ≈ 3 min to complete
• Tools: privacy.sexy
• Difficulty: Simple
• ≈ 4 instructions

privacy.sexy is free and open-source application that lets securely apply this action easily with more advanced options.

1. 1

   Open or download

   Open or download the desktop application
2. 2

   Choose script

   1. Search for the script name: Clear previous Windows installations
   2. Check the script by clicking on the checkbox.
3. 3

   Run

   Click on ▶️ Run button at the bottom of the page.

   This button only appears on desktop version (recommended). On browser, use 💾 Save button.

Run commands

Copy and run commands manually Requires technical knowledge

Apply

Apply changes

:: Delete directory (with additional permissions) : "%SYSTEMDRIVE%\Windows.old"
PowerShell -ExecutionPolicy Unrestricted -Command "$pathGlobPattern = "^""$($directoryGlob = '%SYSTEMDRIVE%\Windows.old'; if (-Not $directoryGlob.EndsWith('\')) { $directoryGlob += '\' }; $directoryGlob )"^""; $expandedPath = [System.Environment]::ExpandEnvironmentVariables($pathGlobPattern); Write-Host "^""Searching for items matching pattern: `"^""$($expandedPath)`"^""."^""; <# Not using `Get-Acl`/`Set-Acl` to avoid adjusting token privileges #>; $parentDirectory = [System.IO.Path]::GetDirectoryName($expandedPath); $fileName = [System.IO.Path]::GetFileName($expandedPath); if ($parentDirectory -like '*[*?]*') { throw "^""Unable to grant permissions to glob path parent directory: `"^""$parentDirectory`"^"", wildcards in parent directory are not supported by ``takeown`` and ``icacls``."^""; }; if (($fileName -ne '*') -and ($fileName -like '*[*?]*')) { throw "^""Unable to grant permissions to glob path file name: `"^""$fileName`"^"", wildcards in file name is not supported by ``takeown`` and ``icacls``."^""; }; Write-Host "^""Taking ownership of `"^""$expandedPath`"^""."^""; $cmdPath = $expandedPath; if ($cmdPath.EndsWith('\')) { $cmdPath += '\' <# Escape trailing backslash for correct handling in batch commands #>; }; $takeOwnershipCommand = "^""takeown /f `"^""$cmdPath`"^"" /a"^"" <# `icacls /setowner` does not succeed, so use `takeown` instead. #>; if (-not (Test-Path -Path "^""$expandedPath"^"" -PathType Leaf)) { $localizedYes = 'Y' <# Default 'Yes' flag (fallback) #>; try { $choiceOutput = cmd /c "^""choice <nul 2>nul"^""; if ($choiceOutput -and $choiceOutput.Length -ge 2) { $localizedYes = $choiceOutput[1]; } else { Write-Warning "^""Failed to determine localized 'Yes' character. Output: `"^""$choiceOutput`"^"""^""; }; } catch { Write-Warning "^""Failed to determine localized 'Yes' character. Error: $_"^""; }; $takeOwnershipCommand += "^"" /r /d $localizedYes"^""; }; $takeOwnershipOutput = cmd /c "^""$takeOwnershipCommand 2>&1"^"" <# `stderr` message is misleading, e.g. "^""ERROR: The system cannot find the file specified."^"" is not an error. #>; if ($LASTEXITCODE -eq 0) { Write-Host "^""Successfully took ownership of `"^""$expandedPath`"^"" (using ``$takeOwnershipCommand``)."^""; } else { Write-Host "^""Did not take ownership of `"^""$expandedPath`"^"" using ``$takeOwnershipCommand``, status code: $LASTEXITCODE, message: $takeOwnershipOutput."^""; <# Do not write as error or warning, because this can be due to missing path, it's handled in next command. #>; <# `takeown` exits with status code `1`, making it hard to handle missing path here. #>; }; Write-Host "^""Granting permissions for `"^""$expandedPath`"^""."^""; $adminSid = New-Object System.Security.Principal.SecurityIdentifier 'S-1-5-32-544'; $adminAccount = $adminSid.Translate([System.Security.Principal.NTAccount]); $adminAccountName = $adminAccount.Value; $grantPermissionsCommand = "^""icacls `"^""$cmdPath`"^"" /grant `"^""$($adminAccountName):F`"^"" /t"^""; $icaclsOutput = cmd /c "^""$grantPermissionsCommand"^""; if ($LASTEXITCODE -eq 3) { Write-Host "^""Skipping, no items available for deletion according to: ``$grantPermissionsCommand``."^""; exit 0; } elseif ($LASTEXITCODE -ne 0) { Write-Host "^""Take ownership message:`n$takeOwnershipOutput"^""; Write-Host "^""Grant permissions:`n$icaclsOutput"^""; Write-Warning "^""Failed to assign permissions for `"^""$expandedPath`"^"" using ``$grantPermissionsCommand``, status code: $LASTEXITCODE."^""; } else { $fileStats = $icaclsOutput | ForEach-Object { $_ -match '\d+' | Out-Null; $matches[0] } | Where-Object { $_ -ne $null } | ForEach-Object { [int]$_ }; if ($fileStats.Count -gt 0 -and ($fileStats | ForEach-Object { $_ -eq 0 } | Where-Object { $_ -eq $false }).Count -eq 0) { Write-Host "^""Skipping, no items available for deletion according to: ``$grantPermissionsCommand``."^""; exit 0; } else { Write-Host "^""Successfully granted permissions for `"^""$expandedPath`"^"" (using ``$grantPermissionsCommand``)."^""; }; }; $deletedCount = 0; $failedCount = 0; $foundAbsolutePaths = @(); Write-Host 'Iterating files and directories recursively.'; try { $foundAbsolutePaths += @(; Get-ChildItem -Path $expandedPath -Force -Recurse -ErrorAction Stop | Select-Object -ExpandProperty FullName; ); } catch [System.Management.Automation.ItemNotFoundException] { <# Swallow, do not run `Test-Path` before, it's unreliable for globs requiring extra permissions #>; }; try { $foundAbsolutePaths += @(; Get-Item -Path $expandedPath -ErrorAction Stop | Select-Object -ExpandProperty FullName; ); } catch [System.Management.Automation.ItemNotFoundException] { <# Swallow, do not run `Test-Path` before, it's unreliable for globs requiring extra permissions #>; }; $foundAbsolutePaths = $foundAbsolutePaths | Select-Object -Unique | Sort-Object -Property { $_.Length } -Descending; if (!$foundAbsolutePaths) { Write-Host 'Skipping, no items available.'; exit 0; }; Write-Host "^""Initiating processing of $($foundAbsolutePaths.Count) items from `"^""$expandedPath`"^""."^""; foreach ($path in $foundAbsolutePaths) { if (-not (Test-Path $path)) { <# Re-check existence as prior deletions might remove subsequent items (e.g., subdirectories). #>; Write-Host "^""Successfully deleted: $($path) (already deleted)."^""; $deletedCount++; continue; }; try { Remove-Item -Path $path -Force -Recurse -ErrorAction Stop; $deletedCount++; Write-Host "^""Successfully deleted: $($path)"^""; } catch { $failedCount++; Write-Warning "^""Unable to delete $($path): $_"^""; }; }; Write-Host "^""Successfully deleted $($deletedCount) items."^""; if ($failedCount -gt 0) { Write-Warning "^""Failed to delete $($failedCount) items."^""; }"

Revert

Restore changes

IiI=

Help

How to apply or restore "Clear previous Windows installations" using commands

• ≈ 2 min to complete
• Tools: Command Prompt
• Difficulty: Medium
• ≈ 3 instructions

View step-by-step guide with screenshots

---

1. 1

   Open Command Prompt

   Open Command Prompt as Administrator.
2. 2

   Copy code

   Copy the code:

   Copy Apply Code Copy Revert Code
3. 3

   Paste & run

   Paste the commands into Command Prompt and press Enter to run.

   Some changes require a system restart to take effect

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Privacy cleanup to protect your data with support of proper personal data control on Windows — Read along, this system calibration illustrates just that. What's eq...

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About the Creators

These people have authored this documentation and written its scripts:

• 

  undergroundwires

  • Certified security professional
  • 7+ years experience securing banks
  • Open-source developer since 2005
  • EU advisor, Public Speaker, Moderator
• Open-Source Contributors

  • Hundreds across the globe
  • Testers, reviewers, developers
  • Companies, military agencies
  • Community since 2017

About Us

Reviewed By

This guide has undergone comprehensive auditing and peer review:

• Expert review by undergroundwires

  • Verified technical accuracy and editorial standards
  • Assessed system impact and user privacy risks

• Public review by large community

  • Privacy enthusiasts and professionals peer-reviewed
  • Millions of end-users tested across different environments

History

We continually monitor our guides, their impact and all other privacy options. We update our guides when new information becomes available. On every update, we publicly store who made the change, what has been changed, why the change was made and when the change was made.

Review Change History Our Change Process