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After attempting to install Ubuntu Desktop 32bit on our HyperV environment - which requires static IP addressing, Ubuntu thinks the network cable is unplugged. It's connected to the correct Team NIC in SCVMM (like 40 or so other servers; which are all working fine) but for some reason it doesn't detect that the cable is "plugged in". I'm going to try Ubuntu Server 64-bit to see if that works.
UPDATE - looks like server has the same problem.