en-US windows computer

Define the order of sources for downloading security intelligence updates

Verified with Windows 11 25H2 — updated on July 30, 2026

Windows 11 25H2

Supported on: At least Windows Server 2012, Windows 8 or Windows RT

Path in the GPO console

Computer Configuration\Administrative Templates\Windows Components\Microsoft Defender Antivirus\Security Intelligence Updates

Description

This policy setting allows you to define the order in which different security intelligence update sources should be contacted. The value of this setting should be entered as a pipe-separated string enumerating the security intelligence update sources in order. Possible values are: “InternalDefinitionUpdateServer”, “MicrosoftUpdateServer”, “MMPC”, and “FileShares” For example: { InternalDefinitionUpdateServer | MicrosoftUpdateServer | MMPC } If you enable this setting, security intelligence update sources will be contacted in the order specified. Once security intelligence updates have been successfully downloaded from one specified source, the remaining sources in the list will not be contacted. If you disable or do not configure this setting, security intelligence update sources will be contacted in a default order.

Registry

HKLM Software\Policies\Microsoft\Windows Defender\Signature Updates

More options available

Options

Define the order of sources for downloading security intelligence updates
FallbackOrder text

MDM / Intune (CSP)

./Device/Vendor/MSFT/Policy/Config/ADMX_MicrosoftDefenderAntivirus/SignatureUpdate_FallbackOrder
Device Since Windows 10, version 2004 with KB5005101 [10.0.19041.1202] and later | Windows 10, version 20H2 with KB5005101 [10.0.19042.1202] and later | Windows 10, version 21H1 with KB5005101 [10.0.19043.1202] and later | Windows 11, version 21H2 [10.0.22000] and later Official mapping (Microsoft Learn)

Multiple CSP matches are possible; the first one was selected.

Microsoft Learn documentation Mapping data: Microsoft Learn (CC BY 4.0)

Export Builder

BETA

Configure the state, scope and options, then generate .reg, PowerShell, Intune and SCCM outputs — or add the setting to a multi-setting collection.

These exports write the registry — this is not a managed GPO.

.reg file

Windows Registry Editor Version 5.00

; Exported from gporais.com
; Policy: Define the order of sources for downloading security intelligence updates
; State: Enabled
; Supported on: At least Windows Server 2012, Windows 8 or Windows RT

[HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows Defender\Signature Updates]
"FallbackOrder"=""
More formats (PowerShell, Intune, SCCM)

PowerShell

# Exported from gporais.com
# Policy: Define the order of sources for downloading security intelligence updates
# State: Enabled
# Supported on: At least Windows Server 2012, Windows 8 or Windows RT

$path = 'HKLM:\Software\Policies\Microsoft\Windows Defender\Signature Updates'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'FallbackOrder' -Value '' -Type String

Building a multi-setting collection? Add this setting and generate combined .reg / PowerShell / GPO scripts.

Open the Builder

Embed this policy on your site

What to embed
Theme

Adds one script line: the theme follows your site’s appearance and the height fits the content. If your site blocks scripts, the embed follows the visitor’s system theme.

Preview