Block macros from running in Office files from the internet
This per-user policy value controls whether Microsoft Access can run macros in Office files that Windows identifies as originating from the internet or another untrusted zone.
since 0.9.8.11
Purpose
Show registry keys (1)
HKCU\software\policies\microsoft\office\16.0\access\security\blockcontentexecutionfrominternet
This per-user policy value controls whether Microsoft Access can run macros in Office files that Windows identifies as originating from the internet or another untrusted zone. That origin is commonly represented by Mark of the Web (MOTW), for example on downloaded files and email attachments.
The value uses the REG_DWORD data type. A value of 1 enables the policy: Access blocks the affected macros even when “Enable all macros” is selected in Trust Center and notifies the user that execution was blocked. A value of 0 disables the policy, leaving the decision to the macro settings configured in Trust Center.
The value applies only to Microsoft Access in the current user’s context. Equivalent policies for other Office applications use separate application-specific registry keys.
Notes
Security
Blocking internet-originated macros reduces exposure to malicious Office files that use macro code to install malware, steal data, or perform other actions with the signed-in user’s permissions. It is not a malware scan and does not establish whether a file is safe; the decision depends on the origin determined by Windows and Office and on the applicable trust settings.
Macros can still run when Office already treats the file or its publisher as trusted. Important cases include files stored in a Trusted Location and correctly signed macros whose publisher certificate is trusted on the device. Treatment of documents that were trusted previously can also vary between Office versions. If another process removes the file’s origin marking, the file is no longer subject to this internet-origin check.
Possible side effects
Features in an affected Access file that depend on macros or VBA code remain unavailable while the code is blocked. This can disrupt automation, event handling, and other database workflows without necessarily preventing the file itself from opening.
Files on internal network shares can also be affected when Windows does not classify the location as part of the Local intranet zone or a trusted zone.
Notes
Current Office versions can block macros from the internet by default even when this policy is not configured. An explicit value of 1 enforces the policy regardless of less restrictive macro selections in Trust Center.
In this context, “from the internet” refers to the security zone determined by Windows and Office. It does not depend solely on where the file is physically or organizationally located.
Microsoft documentation
Microsoft Learn: Macros from the internet are blocked by default in Office