Base URL: registry value customizablealertbaseurlUserHKCU\software\policies\microsoft\office\16.0\common\general

Policy ID: L_BaseURL
Scope: User Configuration
Supported on: At least Windows Server 2008 R2 or Windows 7
Source: Microsoft 365 Apps / Office Administrative Templates (version 5568.1000)
Category: Microsoft Office 2016 › Customizable Error Messages

Registry

customizablealertbaseurl

REG_SZUser

HKCU\software\policies\microsoft\office\16.0\common\general Current key

Enabled value: Depends on the option value
Element: Base URL
Value type: REG_SZ

Apply with .reg · CMD · PowerShell

.reg

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\software\policies\microsoft\office\16.0\common\general]

; Value names and types follow the ADMX. Replace <enter value> below with your own data
"customizablealertbaseurl"="<enter value>"

CMD

:: Value names and types follow the ADMX. Replace <enter value> below with your own data

reg add "HKCU\software\policies\microsoft\office\16.0\common\general" /v "customizablealertbaseurl" /t REG_SZ /d "<enter value>" /f

PowerShell

# Value names and types follow the ADMX. Replace <enter value> below with your own data

New-Item -Path 'HKCU:\software\policies\microsoft\office\16.0\common\general' -Force | Out-Null
New-ItemProperty -Path 'HKCU:\software\policies\microsoft\office\16.0\common\general' -Name 'customizablealertbaseurl' -PropertyType String -Value '<enter value>' -Force | Out-Null