I checked DirectAccess Group policy and the Machine certificate and they were all fine. Its mainly IPV6 in question. Microsoft added native support for IPV6 and its enabled by default starting from Windows Vista and Server 2008. Some users try to disable IPV6 by unchecking the IPV6 option/check box from the Network card properties however this won't disable IPV6.
Microsoft released several Fixit (One click file) to enable, disable or give preference for IPV6 on IPV4 or vice verse instead of digging deeply in the registry to enable or disable IPV6.
Please check these several Fixit on http://support.microsoft.com/kb/929852
In our case IPV6 was disabled and need to be enabled either by using one of the Fixit provided in the link above or by checking the registry as follows:
- Locate the following Registry key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip6\Parameters\
- Check for DisabledComponents under the above key.
- To Enable IPV6 make sure this key has value of Zero or just delete it. If it has any other value IPV6 won't work correctly.
Hopefully this can help anyone encountering the same issue.