I can connect to the network on every try -- but the connection only lasts about a minute, and then the connection is lost. Using a Netgear USB adaptor and Netgear router. (Three other computers work fine on the network -- an iMac, an HP laptop and a Lenovo laptop.) None of the other computers drops off the network. The Lenovo laptop, wihich works just fine is located right at the computer that doesn't stay connected, so it's not a range problem. Ideas appreciated.