Core issue
Authentication for users might fail on the VPN Concentrator while using the Active directory (AD) controller,
The VPN Concentrator throws out the error shown below,
%AUTH-4-5: RPT=267: Authentication rejected: Reason = Unspecified handle
Resolution
To resolve the issue, perform these steps:
- Make sure that time syncronization between the VPN Concentrator and the domain controller is done.
- The domain name must be specified in upper case on the VPN Concentrator.
- Disable preauthentication in the user profile of the domain controller.
For additional information, refer to PPTP to CVPN Concentrator.