We received this unit in what appeared to be good working order. However, the unit only shows a config error and won't come online. We have other working VVX 1500s on our network. I tried to work with the seller via chat to get this returned, but was advised I have to work directly with Polycom. We've only had the unit in hand for 30 days, but was advised that the window to return has closed. I will not purchase from this seller again.