On a Windows Vista-based computer, when you try to communicate with another computer through an Internet Protocol security (IPsec) tunnel-mode connection, the connection fails.

This issue occurs if the Windows Vista-based computer is behind a Network Address Translation (NAT) device.

• Security rules for Windows Firewall and for IPsec-based connections in Windows Vista and in Windows Server 2008
  Details on security rules for the built in firewall, IPsec, and how to establish an encrypted conection between various versions of Windows.
  (tags: Firewall IPsec )
• How the default response rule for IPsec policies functions in Windows Vista and in Windows Server 2008 Beta 3
  Learn about the default response rule for IPsec policies and how to create a replacement rule.
  (tags: IPsec )

Keep reading →

Details on security rules for the built in firewall, IPsec, and how to establish an encrypted conection between various versions of Windows. Keep reading →

Learn about the default response rule for IPsec policies and how to create a replacement rule. Keep reading →

You cannot connect a computer that is running Windows Vista to a Cisco ASA Series VPN server by using a virtual private network (VPN) connection that is based on the “Layer 2 Tunneling Protocol with IPsec” (L2TP/IPsec) protocol. This problem occurs if another Windows Vista-based computer is already connecting to the VPN server through a L2TP/IPsec-based VPN connection. You cannot connect to the VPN server until the other computer disconnects from the VPN server.

This behavior does not occur on a computer that is running Windows XP or Windows Server 2003.

When you use an Internet Protocol security (IPsec) tunnel mode connection to communicate from a Windows Vista-based computer to another computer, the Windows Vista-based computer may restart. Also, you may receive an error message that resembles the following:

STOP 0×000000D1 (parameter1, parameter2, parameter3, parameter4)
DRIVER_IRQL_NOT_LESS_OR_EQUAL

This problem occurs if you install antivirus filter drivers on the Windows Vista-based computer.

When you try to enroll for an IPsec certificate or for a computer certificate in Windows Vista, the certificate may not be enrolled. You do not receive an error message, and an event is not logged.

You experience one of the following symptoms when you try to establish a virtual private network (VPN) connection by using “Layer Two Tunneling Protocol with IPsec” (L2TP/IPsec) from a Windows client computer to a VPN server.

• Symptom 1

  The Windows client computer is running Microsoft Windows XP, Microsoft Windows Server 2003, or Microsoft Windows 2000, and you try to connect to a VPN server that is running Microsoft Windows Server Code Name “Longhorn” or Windows Vista. However, you cannot connect to the VPN server. Instead, you receive an error message the resembles the following:

  741 The local computer does not support encryption.

• Symptom 2

  The Windows client computer is running Windows Server Code Name “Longhorn” or Windows Vista, and you try to connect to a VPN server that is running Windows XP, Windows Server 2003, or Windows 2000. However, you cannot connect to the VPN server. Instead, you receive an error message the resembles the following:

  742 The remote server does not support encryption.