I had a battle with a Windows Server 2008 machine. It’s TCP/IP default gateway disappears upon reboot. I tried to retype the default gateway and reboot many times. It seemed like a strange issue.
If above links are not working, following the instructions below.
netsh int ip reset c:resetlog.txt
Reboot the server and re-type the IP address if it is static address.
Note If you do not want to specify a directory path for the log file, use the following command:
netsh int ip reset resetlog.txt
Optionally you can also reset the winsock with the following command:
netsh winsock reset catalog
Hope this helps you when you need it.