Functions/GenXdev.Windows/Set-KnownFolderPath.ps1

<##############################################################################
Part of PowerShell module : GenXdev.Windows
Original cmdlet filename : Set-KnownFolderPath.ps1
Original author : René Vaessen / GenXdev
Version : 1.264.2025
################################################################################
MIT License
 
Copyright 2021-2025 GenXdev
 
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
 
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
 
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
################################################################################>

###############################################################################

###############################################################################define known folder guids for windows shell api
$knownFolders = @{
    '3DObjects'             = '31C0DD25-9439-4F12-BF41-7FF4EDA38722';
    'AddNewPrograms'        = 'de61d971-5ebc-4f02-a3a9-6c82895e5c04';
    'AdminTools'            = '724EF170-A42D-4FEF-9F26-B60E846FBA4F';
    'AppUpdates'            = 'a305ce99-f527-492b-8b1a-7e76fa98d6e4';
    'CDBurning'             = '9E52AB10-F80D-49DF-ACB8-4330F5687855';
    'ChangeRemovePrograms'  = 'df7266ac-9274-4867-8d55-3bd661de872d';
    'CommonAdminTools'      = 'D0384E7D-BAC3-4797-8F14-CBA229B392B5';
    'CommonOEMLinks'        = 'C1BAE2D0-10DF-4334-BEDD-7AA20B227A9D';
    'CommonPrograms'        = '0139D44E-6AFE-49F2-8690-3DAFCAE6FFB8';
    'CommonStartMenu'       = 'A4115719-D62E-491D-AA7C-E74B8BE3B067';
    'CommonStartup'         = '82A5EA35-D9CD-47C5-9629-E15D2F714E6E';
    'CommonTemplates'       = 'B94237E7-57AC-4347-9151-B08C6C32D1F7';
    'ComputerFolder'        = '0AC0837C-BBF8-452A-850D-79D08E667CA7';
    'ConflictFolder'        = '4bfefb45-347d-4006-a5be-ac0cb0567192';
    'ConnectionsFolder'     = '6F0CD92B-2E97-45D1-88FF-B0D186B8DEDD';
    'Contacts'              = '56784854-C6CB-462b-8169-88E350ACB882';
    'ControlPanelFolder'    = '82A74AEB-AEB4-465C-A014-D097EE346D63';
    'Cookies'               = '2B0F765D-C0E9-4171-908E-08A611B84FF6';
    'Desktop'               = 'B4BFCC3A-DB2C-424C-B029-7FE99A87C641';
    'Documents'             = 'FDD39AD0-238F-46AF-ADB4-6C85480369C7';
    'Downloads'             = '374DE290-123F-4565-9164-39C4925E467B';
    'Favorites'             = '1777F761-68AD-4D8A-87BD-30B759FA33DD';
    'Fonts'                 = 'FD228CB7-AE11-4AE3-864C-16F3910AB8FE';
    'Games'                 = 'CAC52C1A-B53D-4edc-92D7-6B2E8AC19434';
    'GameTasks'             = '054FAE61-4DD8-4787-80B6-090220C4B700';
    'History'               = 'D9DC8A3B-B784-432E-A781-5A1130A75963';
    'InternetCache'         = '352481E8-33BE-4251-BA85-6007CAEDCF9D';
    'InternetFolder'        = '4D9F7874-4E0C-4904-967B-40B0D20C3E4B';
    'Links'                 = 'bfb9d5e0-c6a9-404c-b2b2-ae6db6af4968';
    'LocalAppData'          = 'F1B32785-6FBA-4FCF-9D55-7B8E7F157091';
    'LocalAppDataLow'       = 'A520A1A4-1780-4FF6-BD18-167343C5AF16';
    'LocalizedResourcesDir' = '2A00375E-224C-49DE-B8D1-440DF7EF3DDC';
    'Music'                 = '4BD8D571-6D19-48D3-BE97-422220080E43';
    'NetHood'               = 'C5ABBF53-E17F-4121-8900-86626FC2C973';
    'NetworkFolder'         = 'D20BEEC4-5CA8-4905-AE3B-BF251EA09B53';
    'OriginalImages'        = '2C36C0AA-5812-4b87-BFD0-4CD0DFB19B39';
    'PhotoAlbums'           = '69D2CF90-FC33-4FB7-9A0C-EBB0F0FCB43C';
    'Pictures'              = '33E28130-4E1E-4676-835A-98395C3BC3BB';
    'Playlists'             = 'DE92C1C7-837F-4F69-A3BB-86E631204A23';
    'PrintersFolder'        = '76FC4E2D-D6AD-4519-A663-37BD56068185';
    'PrintHood'             = '9274BD8D-CFD1-41C3-B35E-B13F55A758F4';
    'Profile'               = '5E6C858F-0E22-4760-9AFE-EA3317B67173';
    'ProgramData'           = '62AB5D82-FDC1-4DC3-A9DD-070D1D495D97';
    'ProgramFiles'          = '905e63b6-c1bf-494e-b29c-65b732d3d21a';
    'ProgramFilesX64'       = '6D809377-6AF0-444b-8957-A3773F02200E';
    'ProgramFilesX86'       = '7C5A40EF-A0FB-4BFC-874A-C0F2E0B9FA8E';
    'ProgramFilesCommon'    = 'F7F1ED05-9F6D-47A2-AAAE-29D317C6F066';
    'ProgramFilesCommonX64' = '6365D5A7-0F0D-45E5-87F6-0DA56B6A4F7D';
    'ProgramFilesCommonX86' = 'DE974D24-D9C6-4D3E-BF91-F4455120B917';
    'Programs'              = 'A77F5D77-2E2B-44C3-A6A2-ABA601054A51';
    'Public'                = 'DFDF76A2-C82A-4D63-906A-5644AC457385';
    'PublicDesktop'         = 'C4AA340D-F20F-4863-AFEF-F87EF2E6BA25';
    'PublicDocuments'       = 'ED4824AF-DCE4-45A8-81E2-FC7965083634';
    'PublicDownloads'       = '3D644C9B-1FB8-4f30-9B45-F670235F79C0';
    'PublicGameTasks'       = 'DEBF2536-E1A8-4c59-B6A2-414586476AEA';
    'PublicMusic'           = '3214FAB5-9757-4298-BB61-92A9DEAA44FF';
    'PublicPictures'        = 'B6EBFB86-6907-413C-9AF7-4FC2ABF07CC5';
    'PublicVideos'          = '2400183A-6185-49FB-A2D8-4A392A602BA3';
    'QuickLaunch'           = '52a4f021-7b75-48a9-9f6b-4b87a210bc8f';
    'Recent'                = 'AE50C081-EBD2-438A-8655-8A092E34987A';
    'RecycleBinFolder'      = 'B7534046-3ECB-4C18-BE4E-64CD4CB7D6AC';
    'ResourceDir'           = '8AD10C31-2ADB-4296-A8F7-E4701232C972';
    'RoamingAppData'        = '3EB685DB-65F9-4CF6-A03A-E3EF65729F3D';
    'SampleMusic'           = 'B250C668-F57D-4EE1-A63C-290EE7D1AA1F';
    'SamplePictures'        = 'C4900540-2379-4C75-844B-64E6FAF8716B';
    'SamplePlaylists'       = '15CA69B3-30EE-49C1-ACE1-6B5EC372AFB5';
    'SampleVideos'          = '859EAD94-2E85-48AD-A71A-0969CB56A6CD';
    'SavedGames'            = '4C5C32FF-BB9D-43b0-B5B4-2D72E54EAAA4';
    'SavedSearches'         = '7d1d3a04-debb-4115-95cf-2f29da2920da';
    'SEARCH_CSC'            = 'ee32e446-31ca-4aba-814f-a5ebd2fd6d5e';
    'SEARCH_MAPI'           = '98ec0e18-2098-4d44-8644-66979315a281';
    'SearchHome'            = '190337d1-b8ca-4121-a639-6d472d16972a';
    'SendTo'                = '8983036C-27C0-404B-8F08-102D10DCFD74';
    'SidebarDefaultParts'   = '7B396E54-9EC5-4300-BE0A-2482EBAE1A26';
    'SidebarParts'          = 'A75D362E-50FC-4fb7-AC2C-A8BEAA314493';
    'StartMenu'             = '625B53C3-AB48-4EC1-BA1F-A1EF4146FC19';
    'Startup'               = 'B97D20BB-F46A-4C97-BA10-5E3608430854';
    'SyncManagerFolder'     = '43668BF8-C14E-49B2-97C9-747784D784B7';
    'SyncResultsFolder'     = '289a9a43-be44-4057-a41b-587a76d7e7f9';
    'SyncSetupFolder'       = '0F214138-B1D3-4a90-BBA9-27CBC0C5389A';
    'System'                = '1AC14E77-02E7-4E5D-B744-2EB1AE5198B7';
    'SystemX86'             = 'D65231B0-B2F1-4857-A4CE-A8E7C6EA7D27';
    'Templates'             = 'A63293E8-664E-48DB-A079-DF759E0509F7';
    'TreeProperties'        = '5b3749ad-b49f-49c1-83eb-15370fbd4882';
    'UserProfiles'          = '0762D272-C50A-4BB0-A382-697DCD729B80';
    'UsersFiles'            = 'f3ce0f7c-4901-4acc-8648-d5d44b04ef8f';
    'Videos'                = '18989B1D-99B5-455B-841C-AB7C74E4DDFC';
    'Windows'               = 'F38BF404-1D43-42F2-9305-67DE0B28FC23';
}

###############################################################################

<#
.SYNOPSIS
Modifies the physical path of a Windows known folder.
 
.DESCRIPTION
Uses the Windows Shell32 API to relocate system folders like Documents,
Downloads, Desktop, or other known Windows folders to a new location. The
function validates the target path exists, looks up the folder's unique GUID
from the comprehensive known folders registry, and uses the SHSetKnownFolderPath
API to perform the relocation. Common use cases include moving user folders to
a different drive for space management or organization. Exercise caution when
moving system-critical folders as this may affect system stability.
 
.PARAMETER KnownFolder
The name of the known folder to relocate. Supports all Windows known folders
including user folders (Documents, Downloads, Desktop, Pictures, Videos,
Music), system folders (Windows, System, ProgramFiles), and special folders
(Recent, Favorites, SendTo, etc.). Use with caution as moving certain system
folders may cause instability.
 
.PARAMETER Path
The new physical file system path where the known folder should be located.
The path must exist before attempting the move operation. The function will
throw an error if the path is invalid or inaccessible.
 
.EXAMPLE
Set-KnownFolderPath -KnownFolder 'Documents' -Path 'D:\UserDocs'
 
.EXAMPLE
Set-KnownFolderPath Downloads 'E:\Downloads'
#>

function Set-KnownFolderPath {

    [CmdletBinding(SupportsShouldProcess = $true, ConfirmImpact = 'High')]
    param(
        ###################################################################
        [Parameter(
            Position = 0,
            Mandatory = $true,
            HelpMessage = 'Known folder to modify'
        )]
        [ValidateSet('3DObjects', 'AddNewPrograms', 'AdminTools',
            'AppUpdates', 'CDBurning', 'ChangeRemovePrograms',
            'CommonAdminTools', 'CommonOEMLinks', 'CommonPrograms',
            'CommonStartMenu', 'CommonStartup', 'CommonTemplates',
            'ComputerFolder', 'ConflictFolder', 'ConnectionsFolder',
            'Contacts', 'ControlPanelFolder', 'Cookies', 'Desktop',
            'Documents', 'Downloads', 'Favorites', 'Fonts', 'Games',
            'GameTasks', 'History', 'InternetCache', 'InternetFolder',
            'Links', 'LocalAppData', 'LocalAppDataLow',
            'LocalizedResourcesDir', 'Music', 'NetHood',
            'NetworkFolder', 'OriginalImages', 'PhotoAlbums',
            'Pictures', 'Playlists', 'PrintersFolder', 'PrintHood',
            'Profile', 'ProgramData', 'ProgramFiles', 'ProgramFilesX64',
            'ProgramFilesX86', 'ProgramFilesCommon',
            'ProgramFilesCommonX64', 'ProgramFilesCommonX86',
            'Programs', 'Public', 'PublicDesktop', 'PublicDocuments',
            'PublicDownloads', 'PublicGameTasks', 'PublicMusic',
            'PublicPictures', 'PublicVideos', 'QuickLaunch', 'Recent',
            'RecycleBinFolder', 'ResourceDir', 'RoamingAppData',
            'SampleMusic', 'SamplePictures', 'SamplePlaylists',
            'SampleVideos', 'SavedGames', 'SavedSearches', 'SEARCH_CSC',
            'SEARCH_MAPI', 'SearchHome', 'SendTo', 'SidebarDefaultParts',
            'SidebarParts', 'StartMenu', 'Startup', 'SyncManagerFolder',
            'SyncResultsFolder', 'SyncSetupFolder', 'System',
            'SystemX86', 'Templates', 'TreeProperties', 'UserProfiles',
            'UsersFiles', 'Videos', 'Windows')]
        [string] $KnownFolder,
        ###################################################################
        [Parameter(
            Position = 1,
            Mandatory = $true,
            HelpMessage = 'New path for the known folder'
        )]
        [ValidateNotNullOrEmpty()]
        [Alias('FullName')]
        [string] $Path
        ###################################################################
    )

    begin {

        # check if shell32 api type is already loaded to avoid redefining
        $type = ([System.Management.Automation.PSTypeName]`
                'KnownFolders.SHSetKnownFolderPathPS').Type

        if (-not $type) {

            # define windows api function signature for shell32.dll import
            $signature = @'
[DllImport("shell32.dll")]
public extern static int SHSetKnownFolderPath(ref Guid folderId, uint flags,
    IntPtr token, [MarshalAs(UnmanagedType.LPWStr)] string path);
'@


            # load the shell32 api function into powershell runtime
            $type = Microsoft.PowerShell.Utility\Add-Type `
                -MemberDefinition $signature `
                -Namespace 'KnownFolders' `
                -Name 'SHSetKnownFolderPathPS' `
                -PassThru
        }

        Microsoft.PowerShell.Utility\Write-Verbose (
            'Starting known folder path change operation'
        )

        Microsoft.PowerShell.Utility\Write-Verbose (
            "Target folder: $KnownFolder"
        )

        Microsoft.PowerShell.Utility\Write-Verbose (
            "New path: $Path"
        )
    }

    process {

        # verify the destination path exists before attempting to move
        if (-not (Microsoft.PowerShell.Management\Test-Path `
                    -LiteralPath $Path `
                    -PathType Container)) {

            $msg = "Could not find folder path: $Path"

            Microsoft.PowerShell.Utility\Write-Error -Message $msg

            throw [System.IO.DirectoryNotFoundException] $msg
        }

        # lookup the folder's unique guid from our hash table
        $knownFolderId = $knownFolders[$KnownFolder]

        Microsoft.PowerShell.Utility\Write-Verbose (
            "Found folder GUID: $knownFolderId"
        )

        if ($PSCmdlet.ShouldProcess($Path, "Set $KnownFolder location")) {

            # call shell32 api to perform the folder relocation
            # parameters: folderId (ref), flags (0), token (0), new path
            $result = $type::SHSetKnownFolderPath([ref]$knownFolderId, 0, 0,
                $Path)

            Microsoft.PowerShell.Utility\Write-Verbose (
                "Shell API call completed with result: $result"
            )

            return $result
        }
    }

    end {
    }
}