Err Msg: Intermittent RAS "Error 5: Access Denied" Error When Tunneling into a PPTP Server

ID: Q222060

The information in this article applies to:

SYMPTOMS

When you attempt to make a PPTP connection from a Windows NT 4.0 Service Pack 4 (SP4) client to a Windows NT 4.0 SP4 PPTP server running RAS or Routing and Remote Access Service (RRAS), the initial authentication attempt may not work and display an "Error 5: Access Denied" error message. This problem can also occur if your PPTP client and server are running the post-Service Pack 3 PPTP3-fix hotfix.


CAUSE

This problem occurs because there is a timing mismatch during the authentication process between the client and server using MSCHAPv2 authentication.


RESOLUTION

To resolve this problem, obtain the latest service pack for Microsoft Windows NT 4.0. For additional information, please see the following article in the Microsoft Knowledge Base:

Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack


STATUS

Microsoft has confirmed this to be a problem in Windows NT 4.0. This problem was first corrected in Windows NT 4.0 Service Pack 5.


MORE INFORMATION

The hotfix must be applied to the PPTP client computer, installing the hotfix or Windows NT 4.0 Service Pack 5 (SP5) to the PPTP server will not fix this problem. In the very rare case where the client is another RRAS server, there is also a RRAS-specific fix available if you choose to not install SP5.

Additional query words: pptp authentication MSCHAP MSCHAPv2 RRAS RAS 


Keywords          : kbnetwork kbbug4.00 kbfix4.00 nt4sp5fix 
Version           : winnt:4.0,4.0 SP3,4.0 SP4
Platform          : winnt 
Issue type        : kbbug

Last Reviewed: July 2, 1999