Windows Server 2025 File Explorer shell protocol must run in protected mode.

The shell protocol will limit the set of folders that applications can open when run in protected mode. Restricting files an application can open to a limited set of folders increases the security of Windows.

The default behavior is for shell protected mode to be turned on for File Explorer.

If the registry value name below does not exist, this is not a finding.

If it exists and is configured with a value of "0", this is not a finding.

If it exists and is configured with a value of "1", this is a finding.

Registry Hive: HKEY_LOCAL_MACHINE Registry Path: \SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\Explorer\

Value Name: PreXPSP2ShellProtocolBehavior

Value Type: REG_DWORD Value: 0x00000000 (0) (or if the Value Name does not exist)

The default behavior is for shell protected mode to be turned on for File Explorer.

To correct this, configure the policy value for Computer Configuration >> Administrative Templates >> Windows Components >> File Explorer >> Turn off shell protocol protected mode to "Not Configured" or "Disabled".