I have a dell OptiPlex 790 running Windows 7 Pro. It is experiencing network issue recently. The computer is joined to an AD network, everything works fine until I did shut down and restart. The network is disconnected, it cannot access network driver, nor any website.
So, I take the computer out of AD, then restart. Internet comes back on, and everything is fine. But, once I rejoin it to the AD, then the network goes down again.