This article applies to:

• SWG 10.x
• Windows Vista or Windows 7 clients

Symptoms:

• Trying to configure authentication against Microsoft AD 2008 R2.
• With Windows XP clients, authentication is successful when you disable NTLM V2 enforcement.
• However with Windows 7 or Windows Vista clients, you see "Authentication failure" in the weblog viewer.

Causes:

• This problem occurs because of an additional security check in Windows Server 2008 and Windows Vista.
• This problem is limited to clients that use NTLMv2 authentication without extended security.

Resolution:

To resolve this issue , you can install and configure a Hotfix that Microsoft provides for this issue. See the following Microsoft Knowledge Base article:

• http://support.microsoft.com/kb/957441