en-US office user

Block send when web add-ins can't load

Verified with Microsoft 365/Office 5568.1000 — updated on September 4, 2026

Microsoft 365/Office 5568.1000

Supported on: At least Windows Server 2008 R2 or Windows 7

Path in the GPO console

User Configuration\Administrative Templates\Microsoft Outlook 2016\Security\Trust Center

Description

This policy setting allows you to control whether Outlook should block sending emails and meeting requests until web add-ins are loaded from Exchange. If you enable this policy setting, Outlook won’t allow emails and meeting requests to be sent until web add-ins are loaded from Exchange. If you disable or don’t configure this policy setting, Outlook will allow emails and meeting requests to be sent even if the latest web add-ins haven’t been loaded from Exchange yet. For more information about when to use this setting, see https://go.microsoft.com/fwlink/p/?linkid=2161562

Registry

HKCU software\policies\microsoft\office\16.0\outlook\security

Value name: onsendaddinswaitforload

Enabled: onsendaddinswaitforload = 1

Disabled: onsendaddinswaitforload = 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: Block send when web add-ins can't load
; State: Enabled
; Supported on: At least Windows Server 2008 R2 or Windows 7

[HKEY_CURRENT_USER\software\policies\microsoft\office\16.0\outlook\security]
"onsendaddinswaitforload"=dword:00000001
More formats (PowerShell, Intune, SCCM)

PowerShell

# Exported from gporais.com
# Policy: Block send when web add-ins can't load
# State: Enabled
# Supported on: At least Windows Server 2008 R2 or Windows 7
# Warning: In SYSTEM context (the Intune default), HKCU targets the SYSTEM profile. Run this script using the logged-on credentials.

$path = 'HKCU:\software\policies\microsoft\office\16.0\outlook\security'
New-Item -Path $path -Force | Out-Null
Set-ItemProperty -Path $path -Name 'onsendaddinswaitforload' -Value 1 -Type DWord

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

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