Allow Trusted Locations on the network
This per-user registry value controls whether Microsoft Access can use network paths as Trusted Locations.
since 0.9.8.11
Purpose
Show registry keys (1)
HKCU\software\policies\microsoft\office\16.0\access\security\trusted locations\allownetworklocations
This per-user registry value controls whether Microsoft Access can use network paths as Trusted Locations. Its type is REG_DWORD.
A value of 1 permits explicitly designated network paths to operate as Trusted Locations. This includes locations defined by users and locations deployed through policy. It does not automatically trust every network folder or grant access to network resources.
A value of 0 causes Access to ignore all network-based Trusted Locations, including locations defined centrally through policy. It also prevents users from adding new network paths as Trusted Locations. Existing entries are not deleted, but they remain ineffective while network locations are blocked.
Notes
Additional effects
Access treats files in an effective Trusted Location as safe. Such files bypass checks including file validation and File Block, and they do not open in Protected View or Application Guard. Active content—including VBA macros, ActiveX controls, add-ins, and external data connections—can be enabled without the security warnings that would otherwise apply.
Security
The security of a trusted network folder depends heavily on its share and file permissions. If an attacker or an insufficiently restricted user can add or modify files in that folder, Access can load malicious active content while bypassing the checks and warnings normally applied to the file. This can put the user's computer and accessible data at risk.
The registry value does not itself grant write access to a network folder or confer general Access or Windows privileges. Exposure arises only when an accessible network path has also been designated as trusted and contains malicious or tampered files.
Possible side effects
With a value of 0, Access databases and other files might no longer behave as expected if their macros, add-ins, or other active content previously relied on a trusted network path. Security prompts or protective controls can reappear, and policy-defined Trusted Locations that point to network resources are ignored as well.
Notes
If the value is absent from the Policies branch, the policy is not configured; this is not necessarily equivalent to enforcing a value of 0. Network locations are initially blocked, but users can enable the corresponding Access option themselves unless another policy prevents them from doing so.
This value applies to Microsoft Access for the current user. Similarly named values for other Office applications are separate settings.
Microsoft documentation
Microsoft Learn: Trusted Locations for Office files