Forum Discussion

Brass Contributor

Mar 19, 2024

NTLMv1 authentication

I know this is long overdue, but in pursuit. I have identified our Radius servers (Windows Server 2019 NPS) as the main source of NTLMv1 authentications taking place. I want to disable NTLMv1 and LM...

Copper Contributor

Jul 06, 2025

Please refer to this article, you can enable NTLMv2 authentication by adding this registry entry.

https://learn.microsoft.com/en-us/troubleshoot/windows-server/networking/rras-vpn-connections-fail-ms-chapv2-authentication

Select Start > Run, type regedit in the Open box, and then select OK.
Locate and select the following registry subkey:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\RemoteAccess\Policy
On the Edit menu, point to New, and then select DWORD Value.
Type Enable NTLMv2 Compatibility, and then press ENTER.
On the Edit menu, select Modify.
In the Value data box, type 1, and then select OK.
Exit Registry Editor.