Allow Trusted Locations on the network
This per-user Word policy controls whether network paths can function as Trusted Locations.
since 0.9.8.11
Purpose
Show registry keys (1)
HKCU\software\policies\microsoft\office\16.0\word\security\trusted locations\allownetworklocations
This per-user Word policy controls whether network paths can function as Trusted Locations. When the policy is enabled, Word can recognize network locations defined either by policy or by the user as trusted.
Enabling the policy does not make every network path trusted. A specific folder must also be designated as a Trusted Location.
When the policy is disabled, Word blocks network-based Trusted Locations, including locations supplied through another administrative policy. It ignores network locations previously added by the user and prevents the user from adding new ones.
Notes
Security
Word assumes that files opened from an effective Trusted Location are safe. Such files bypass protections including file validation, File Block settings, Protected View, and Application Guard. Active content—including VBA macros, ActiveX controls, add-ins, and external data connections—can be allowed without the security prompts that would otherwise apply.
The security of a network-based Trusted Location therefore depends on its share and file-system permissions. An attacker who can add or modify files in that location could introduce active content that executes when an authorized user opens the file. This policy does not itself grant the attacker access to the network location or any additional file permissions.
The Microsoft 365 Apps security baseline recommends blocking network-based Trusted Locations.
Notes
This setting applies only to Word and to the user represented by the registry hive. It does not change the corresponding Trusted Locations settings for other Office applications.
The Disable all trusted locations policy can prevent all Trusted Locations from being used regardless of this setting. A separate policy governing the mix of policy-defined and user-defined locations can also restrict whether users may create their own Trusted Locations.
Microsoft documentation
Microsoft Learn: Trusted Locations for Office files