Today I had a customer who installed our VM Image on his Hyper-V Server. We could ping the Network Card as the Server was booting. But when the Login Prompt came, the Network Card dropped off. After tring serveral different Things, we started to shut down different Services. And finally we shut off irqbalance. The Network worked after a restart. We turned on all the other Services and it continued working. He is going to reinstall the Server as we tried many different Things including installing some Software packets. What effect this has on the Server, time will only tell.