To manually workaround this issue you need to jump into the registry to enable ICS.
This is usually deployed via Group Policy on a domain network.
As usual, be careful editing the registry.
- Start > Run > gpedit.msc
- Computer Configuration/Administrative Templates/Network/Network Connections
- Disable the following policies;
- Prohibit installation and configuration of Network Bridge on your DNS domain network
- Prohibit use of Internet Connection Firewall on your DNS domain network
- Prohibit use of Internet Connection Sharing on your DNS domain network
- Require domain users to elevate when setting a network’s location
- Start > Run > regedit
- Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\Network Connections
- Add/update a registry DWORD entry for the following, and set it to 1;
Thanks to Jeff for the find.