I have installed the PRO/1000 PT Dual Port Server Adapter in Core 2008 R2 and Device Manager shows exclaimation marks.
I have downloaded the latest drivers (15.8.1) and tried both pnputil and DxSetup.exe, rebooted and still no signs of success.
I would be grateful for confirmation that this adapter should work on Windows Server Core 2008 R2.
If you go into the properties, does it give you any additional information, like a Code 31 or something?
We also have a community dedicated to just network cards over at http://communities.intel.com/community/wired , if you don't get much response here.