I have my own lab server at home and the other day I finally reinstalled it with Windows Server 2012 RC. One of the NICs in the server is an Intel® PRO/1000 GT Desktop Adapter which is connected to a VLAN trunk in one of my switches to be able to put VMs on different VLANS. To configure the NIC to be a VLAN trunk you historically needed to download drivers from Intel.
Herein lies the problem. Intel does not provide new drivers for Windows 7/2008R2. Instead they refer to Microsoft built-in drivers. This means that there is no way that they will provide drivers for Windows Server 2012
After some searching I found a solution:
The only way to find and change advanced settings for the Intel NIC is the Registry. Start regedit and browse to HKLM\SYSTEM\CurrentControlSet\Control\Class\{GUID}\XXXX\VlanFiltering registry key (where {GUID} is the GUID containing the network adapter configuration and XXXX is the NIC to be confgured) and change it from 1 to 0. Then you reboot.
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