disk-space-audit

A small PowerShell file for a full drive on Windows. It shows how much free space each local drive has, which folders under your profile are the biggest, and how big the usual cleanable places are: your TEMP folder, the Windows Update download cache, the Recycle Bin, Downloads and Windows.old. It changes nothing unless you ask. There's one optional cleanup, which runs only when you opt in: it deletes old files from your TEMP folder (or from another folder named Temp or Tmp that you pass with -TempPath), and you can preview it with -WhatIf.

Test status, honestly: the script parses cleanly, PSScriptAnalyzer reports 0 findings, and the Pester tests in tests/ pass. All of that was done with PowerShell 7 on Linux, using fake drives, a fake Recycle Bin and a throwaway test folder. It has not yet been run on a real Windows 11 PC, on Windows 10, or on Windows PowerShell 5.1. Try the cleanup with -WhatIf first.

What it does

Dot-sourcing disk-space-audit.ps1 loads the functions below. Nothing runs and nothing changes until you call one.

Function	Changes anything?	What it does
Get-FixedDriveSpace	No	Lists local fixed drives (Win32_LogicalDisk with DriveType = 3) with size, free GB and percent free.
Get-FolderSize -Path <folder>	No	Adds up file sizes under one folder. It never follows junctions or symbolic links, so links can't make a folder look bigger than it is. It counts folders it couldn't read instead of stopping.
Get-LargestFolder [-Path <folder>] [-Top 10]	No	Measures each folder directly under -Path (default: your user profile) and lists the biggest first.
Get-CleanupCandidate [-OlderThanDays 7]	No	One row each for: user TEMP (total), TEMP files older than N days, %SystemRoot%\SoftwareDistribution\Download, Recycle Bin, Downloads, and Windows.old if it exists. Each row says what to do about it.
Remove-OldTempFile [-OlderThanDays 7]	Yes: deletes files	Deletes files in your user TEMP folder ($env:TEMP) that haven't changed in N days. Asks first (ConfirmImpact = 'High'), supports -WhatIf. Skips hidden and read-only files, files in use, and anything behind a junction or symbolic link.

What it does not delete: Downloads, the Recycle Bin, the Windows Update cache and Windows.old are only measured. For those:

• Recycle Bin: look inside first, then use PowerShell's built-in Clear-RecycleBin -WhatIf, then Clear-RecycleBin. Don't add -Force: Microsoft's docs say it also overrides -WhatIf and -Confirm.
• Downloads: these are your files. Sort by size in File Explorer and decide yourself.
• Windows Update cache and Windows.old: use Settings > System > Storage > Cleanup recommendations (or Disk Cleanup). Removing Windows.old means you can't go back to your previous version of Windows.
• Storage Sense (Settings > System > Storage) can clear temporary files and the Recycle Bin automatically.

How to run it

1. Download disk-space-audit.ps1 and read it (about 270 lines of plain text).

2. Open PowerShell. A normal (non-admin) window is enough. Some system folders can't be read without admin rights, and the script reports them in the Unreadable count rather than failing.

3. If PowerShell refuses to run scripts, allow them for this window only, and unblock the file you have read:

   Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope Process
   Unblock-File -Path .\disk-space-audit.ps1

   -Scope Process lasts until you close the window. Your normal execution policy stays the same.

4. Load the functions (note the leading dot and space) and look around:

   . .\disk-space-audit.ps1
   Get-FixedDriveSpace | Format-Table -AutoSize
   Get-LargestFolder -Top 10 | Format-Table Folder, SizeGB, Files -AutoSize
   Get-CleanupCandidate | Format-Table Location, SizeGB, Advice -Wrap

5. Optional cleanup, previewing first:

   Remove-OldTempFile -OlderThanDays 7 -WhatIf
   Remove-OldTempFile -OlderThanDays 7

Measuring a big profile can take a few minutes. Use -Path to look at one folder at a time, for example Get-LargestFolder -Path "$env:USERPROFILE\AppData\Local".

-WhatIf, -Confirm and safety (as implemented)

• Remove-OldTempFile declares SupportsShouldProcess with ConfirmImpact = 'High', so it asks before deleting even without -Confirm. With -WhatIf it prints one line (how many files, how many MB) and deletes nothing. Add -Confirm:$false to skip the prompt once you trust it.
• It refuses to run if $env:TEMP is empty, missing, or points at a folder that isn't named Temp or Tmp. That way a broken TEMP variable can't aim it at your profile or the Windows folder.
• It walks the folder itself and never goes into a junction or symbolic link, so it can't reach files outside TEMP.
• It calls Remove-Item without -Force, so hidden and read-only files are left alone. Files that can't be deleted (usually because a running program has them open) are counted as Skipped.
• There's no undo. It only takes files you haven't changed in N days (7 by default) from a folder that's meant for temporary files.
• Sizes are the sum of file lengths. That can differ from "size on disk" in File Explorer, for example for compressed files or OneDrive files that are only stored online.

Tests

Invoke-ScriptAnalyzer -Path . -Recurse -Severity Error,Warning,Information
Invoke-Pester -Path .\tests -Output Detailed

The tests mock Get-CimInstance and the Recycle Bin reader, and build real files and symbolic links only inside Pester's throwaway TestDrive:. They check:

• the drive query asks only for DriveType = 3 and does the GB and percent maths (including a zero-size drive)
• folder sizes add up across subfolders
• a symbolic link to another folder is not followed, by either the size walk or the TEMP walk
• largest-folder sorting and -Top work
• the report rows appear, including Windows.old with its warning, and nothing is deleted
• -WhatIf deletes nothing
• a real run deletes only files older than the cutoff
• a file that can't be deleted is skipped
• a folder not named Temp, or an empty TEMP path, is refused
• ConfirmImpact is High

Last run (Oct 30, 2026, ET): PowerShell 7.4.6 on Linux, PSScriptAnalyzer 1.25.0: 0 findings in the script and in tests/; Pester 6.2.0: 15 passed, 0 failed. Not run on Windows yet. If you run it on Windows 10/11, please open an issue saying what happened.

Sources (Microsoft)

• Free up drive space in Windows (Cleanup recommendations, Storage Sense, Disk Cleanup, Windows.old, Recycle Bin): https://support.microsoft.com/en-us/windows/experience/storage-filemanagement/free-up-drive-space-in-windows
• Manage drive space with Storage Sense: https://support.microsoft.com/en-us/windows/experience/storage-filemanagement/manage-drive-space-with-storage-sense
• Win32_LogicalDisk class (DriveType 3 = Local Disk, FreeSpace and Size in bytes): https://learn.microsoft.com/en-us/windows/win32/cimwin32prov/win32-logicaldisk
• Clear-RecycleBin (-WhatIf, -Confirm, and the -Force warning): https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.management/clear-recyclebin?view=powershell-5.1
• Remove-Item (read-only and hidden files need -Force): https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.management/remove-item?view=powershell-7.5
• ShellSpecialFolderConstants (Recycle Bin = ssfBITBUCKET, 10): https://learn.microsoft.com/en-us/windows/win32/api/shldisp/ne-shldisp-shellspecialfolderconstants
• FolderItem.Size: https://learn.microsoft.com/en-us/windows/win32/shell/folderitem-size
• KNOWNFOLDERID (Downloads = %USERPROFILE%\Downloads by default): https://learn.microsoft.com/en-us/windows/win32/shell/knownfolderid
• Get-ChildItem (symbolic links and junctions): https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.management/get-childitem
• Set-ExecutionPolicy: https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.security/set-executionpolicy?view=powershell-5.1
• Everything you wanted to know about ShouldProcess: https://learn.microsoft.com/en-us/powershell/scripting/learn/deep-dives/everything-about-shouldprocess

License and disclaimers

MIT (see LICENSE). Provided as-is, without warranty. Deleting files can't be undone; back up anything you care about first.

This code and README were written with AI assistance.

Not affiliated with or endorsed by Microsoft. Windows and PowerShell are trademarks of the Microsoft group of companies.

If you want the rest of the fixes (slow startup, full drive, stuck updates) in one place, I sell a 40-page guide with the scripts: Windows 11 Fix-It Guide + PowerShell Toolkit, $19.