Allow mapping folders into Windows Sandbox: registry value AllowMappedFolders and 1 moreComputerHKLM\SOFTWARE\Policies\Microsoft\Windows\Sandbox

Policy ID: AllowMappedFolders
Scope: Computer Configuration
Supported on: At least Windows 11 Pro, Enterprise, or Education with Windows Sandbox
Source: Administrative Templates (.admx) for Windows 11 2026 Update (26H2) (version 1.0)
Category: Windows Components › Windows Sandbox

Registry

AllowMappedFolders

REG_DWORDComputer

HKLM\SOFTWARE\Policies\Microsoft\Windows\Sandbox Current key

Enabled value: 1
Disabled value: 0

Apply with .reg · CMD · PowerShell

.reg

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\Sandbox]

; Options (use only one)
; Enabled
"AllowMappedFolders"=dword:00000001
; Disabled
"AllowMappedFolders"=dword:00000000

CMD

:: Options (use only one)

:: Enabled
reg add "HKLM\SOFTWARE\Policies\Microsoft\Windows\Sandbox" /v "AllowMappedFolders" /t REG_DWORD /d 1 /f
:: Disabled
reg add "HKLM\SOFTWARE\Policies\Microsoft\Windows\Sandbox" /v "AllowMappedFolders" /t REG_DWORD /d 0 /f

PowerShell

# Common: create the key
New-Item -Path 'HKLM:\SOFTWARE\Policies\Microsoft\Windows\Sandbox' -Force | Out-Null

# Options (use only one)
# Enabled
New-ItemProperty -Path 'HKLM:\SOFTWARE\Policies\Microsoft\Windows\Sandbox' -Name 'AllowMappedFolders' -PropertyType DWord -Value 1 -Force | Out-Null
# Disabled
New-ItemProperty -Path 'HKLM:\SOFTWARE\Policies\Microsoft\Windows\Sandbox' -Name 'AllowMappedFolders' -PropertyType DWord -Value 0 -Force | Out-Null

AllowWriteToMappedFolders

REG_DWORDComputer

HKLM\SOFTWARE\Policies\Microsoft\Windows\Sandbox Current key

Checked: 1
Unchecked: 0
Element: Allow Sandbox to write to mapped folders.
Value type: REG_DWORD

Apply with .reg · CMD · PowerShell

.reg

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\Sandbox]

; Options (use only one)
; Checked
"AllowWriteToMappedFolders"=dword:00000001
; Unchecked
"AllowWriteToMappedFolders"=dword:00000000

CMD

:: Options (use only one)

:: Checked
reg add "HKLM\SOFTWARE\Policies\Microsoft\Windows\Sandbox" /v "AllowWriteToMappedFolders" /t REG_DWORD /d 1 /f
:: Unchecked
reg add "HKLM\SOFTWARE\Policies\Microsoft\Windows\Sandbox" /v "AllowWriteToMappedFolders" /t REG_DWORD /d 0 /f

PowerShell

# Common: create the key
New-Item -Path 'HKLM:\SOFTWARE\Policies\Microsoft\Windows\Sandbox' -Force | Out-Null

# Options (use only one)
# Checked
New-ItemProperty -Path 'HKLM:\SOFTWARE\Policies\Microsoft\Windows\Sandbox' -Name 'AllowWriteToMappedFolders' -PropertyType DWord -Value 1 -Force | Out-Null
# Unchecked
New-ItemProperty -Path 'HKLM:\SOFTWARE\Policies\Microsoft\Windows\Sandbox' -Name 'AllowWriteToMappedFolders' -PropertyType DWord -Value 0 -Force | Out-Null