Windows Server 2008R2 missing gateway IP address

OK so this one was fun.  Guess we can't test every scenario in the real world right?

We had several Windows 2008R2 servers that would not have an IPV4 gateway IP address after a reboot. If I entered one and saved it, then went back and looked, it would be gone again immediately. These machines were ESXi5 VMs but that should not have mattered, you'll see why.

I saw lots of articles about going into the registry and adding the gateway IP address when it disappears and cannot be added again normally. Nope. That should not be a fix anyway, more of a hack.
Other articles about deleting the hidden NICs, etc. Still no.

The issue for me was Symantec Enterprise Protection (SEP). Some of the servers here had a version 11 package with firewall, network protection, whatever, enabled. In my defense this was before my time. I do not typically let SEP handle the firewall on server OS's. We upgraded to version 12 package that did not have the firewall enabled. The upgrade from the management console does not call for a reboot because we're all about uptime these days right? Symantec is under the same pressure I'm sure. Well a week or 2 later when our scheduled maintenance patching came around, the machine booted. Bang, no gateway.

The 'no reboot required' install for SEP upgrades works fine normally except in the case when you go from firewall to no firewall. Evidently you need to remove the firewall while still in version 11, or remove SEP version 11 entirely, and reboot, then upgrade.

If you are already stuck with no gateway, like I was, here is the order of things to get back online.

1. Get a version 11 package with the firewall enabled onto a CD or ISO file that you can mount to the Windows OS (because you are unable to get on the network)
2. Uninstall SEP12, you can leave LiveUpdate on.
3. Reboot
4. Reinstall the SEP11 package with firewall
5. Reboot (you should get your gateway back here)
6. Uninstall SEP11 with firewall
7. Reboot
8. Reinstall 12, done.

According to Symantec support, this is a 'known issue' and will be fixed in the next version. How that happens when it is more a problem with the old version, I do not know. Also there have been several releases of version 12 already. If they were going to prompt to uninstall you would think it would have already been instituted.

Anyway hope this helps someone!

Charlie