Notify users if Internet Explorer is not the default web browser: registry value Check_AssociationsUserHKCU\Software\Policies\Microsoft\Internet Explorer\Main

Policy ID: NotifyNotDefaultBrowser
Scope: User Configuration
Supported on: At least Internet Explorer 10.0
Source: Administrative Templates (.admx) for Windows 11 2026 Update (26H2) (version 1.0)
Category: Windows Components › Internet Explorer

Registry

Check_Associations

REG_SZUser

HKCU\Software\Policies\Microsoft\Internet Explorer\Main Current key

Enabled value: yes
Disabled value: no

Apply with .reg · CMD · PowerShell

.reg

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Software\Policies\Microsoft\Internet Explorer\Main]

; Options (use only one)
; Enabled
"Check_Associations"="yes"
; Disabled
"Check_Associations"="no"

CMD

:: Options (use only one)

:: Enabled
reg add "HKCU\Software\Policies\Microsoft\Internet Explorer\Main" /v "Check_Associations" /t REG_SZ /d "yes" /f
:: Disabled
reg add "HKCU\Software\Policies\Microsoft\Internet Explorer\Main" /v "Check_Associations" /t REG_SZ /d "no" /f

PowerShell

# Common: create the key
New-Item -Path 'HKCU:\Software\Policies\Microsoft\Internet Explorer\Main' -Force | Out-Null

# Options (use only one)
# Enabled
New-ItemProperty -Path 'HKCU:\Software\Policies\Microsoft\Internet Explorer\Main' -Name 'Check_Associations' -PropertyType String -Value 'yes' -Force | Out-Null
# Disabled
New-ItemProperty -Path 'HKCU:\Software\Policies\Microsoft\Internet Explorer\Main' -Name 'Check_Associations' -PropertyType String -Value 'no' -Force | Out-Null