Policy
Prevent co-authoring on files with macros for Word
This policy controls whether users will be able to co-author Word documents with macros. Enabling this policy setting will turn off the ability to co-author Word documents with macros. If you disable or don't configure this policy setting, the user will be able to co-author Word documents with macros. Note: This policy setting only applies to subscription versions of Office, such as Microsoft 365 Apps for enterprise.
63cb88c7c96e L_DisableCoauthoringOnDocmFiles Registry
Copy registry mappings
HKCU\software\policies\microsoft\office\16.0\word\coauthoring\disablecoauthondocmfiles (enabled) = 1
HKCU\software\policies\microsoft\office\16.0\word\coauthoring\disablecoauthondocmfiles (disabled) = 0Policy notes
This policy controls whether users will be able to co-author Word documents with macros. Enabling this policy setting will turn off the ability to co-author Word documents with macros. If you disable or don't configure this policy setting, the user will be able to co-author Word documents with macros. Note: This policy setting only applies to subscription versions of Office, such as Microsoft 365 Apps for enterprise.