Recently I face a strange problem with one of my Windows 2003 Servers
The Server is not responding to any kind of network traffic, even if I try to ping the Gateway, the respone is Destination host unreachable.
IP settings are correct, Subnet mask is also correct and the gateway is responding and working correct, network connectivity seem to be OK, So whats the problem.
As later I found that this is a known issue with Windows Server 2003, when the IPSec Database get corrupted, the server no longer will be able to communicate with anything on the network.
This is the KB http://support.microsoft.com/kb/870910
and to fix the problem I need to rebuild the database:
1- delete the following registry subkey and then rebuild the policy:
As you can see from the picture, I dont have the key, its missing for some reason. but if you found it simply remove it
2- now its time to rebuild the database using the command regsvr32 polstore.dll
3- Restart your computer, and confirm that the registry key is created
Now everything should be OK.