Very recently, I came across an issue where the server was not responding to ping command. When checked within the server name resolution was not working. Tried various options like disable/enable NIC, update drivers, change vlan etc and nothing worked. During troubleshoot I once rebooted the server and found that the server was responding to the ping command after the reboot, unfortunately its stop responding after the Windows login screen.
When checked the event logs found the issue was somehow related to the IPSec service. When checked, the serive was not running. Was then able to start the service after registering the DLL file named “polstore.dll” by executing the command.
Manually starting the service IPSec and a reboot fixed the issue.