I just installed second monitors on a couple of computers I support. They are both Dell Optiplex 760 with ATI graphics card which has a proprietary connector to which one connects the supplied Y cable. The other end of the cable has two DVI sockets. I had deployed the computers with one monitor. The users just purchased second monitors and I installed them this morning. I tested moving a window from the primary to secondary monitor on one system but apparently did not do so for the other. The user is reporting that the mouse will not move from the primary to the secondary monitor. I thought he was trying to drag a maximized window, which I know will not work (must be non-maximized) but he says he can not even move the mouse cursor to the secondary monitor. I have not seen this yet as I am working in another building on campus. I tried having him switch the primary monitor to the other one and the mouse moves there but now won't go to the other monitor so it seems like a configuration problem rather than a monitor problem. Any ideas?