I have been running FS9 on windows 7 for about a month now and have come accross this issue.When I am in 2d cockpit view, if i left-click the mouse anywhere on the screen, any taxi-ing a/c; or dynamic scenery;or cockpit instruments will momentarily stutter (less than a second), then carry on as normal. But there seems to be a cumulative affect here, because if I keep on doing it eventually the screen will freeze completely and I have to shut FS9 down. Just setting an aircraft up for flight (resizing the throttle quadrant;moving the atc window to the top of the screen; using the FMC) can cause the screen to freeze completely.While this stuttering/eventual freeze is occuring the frame rates do not drop at all (locked at 30), and observing the cpu/memory behaviour on Task Manager shows no rise or issue at all ?This behaviour only happens in 2d cockpit view. In virtual cockpit or spot view a mouse click does not stutter the screen at all. This happens in full screen or windowed mode, and also happens even when all the FS9 display sliders are pulled back to the left. I use FSUIPC and have tried changing settings in there (stop cockpit resizing) and that makes no difference. I turn windows Aero desktop off when using FS9 but even this setting does not seem to make any difference, the problem is still there. This behaviour happens with both default and addon aircraft, at any airport (default and addon).I have updated my GPU drivers (using 2 different versions) but no change.My specs are :Intel

Which version of FSUIPC are you using? The latest is 3.965. There were a few issues with joystick timeouts and com radios recently which are fixed in 3.965. Don't know if your issue is related to this but just in case.Bill

Which version of FSUIPC are you using? The latest is 3.965. There were a few issues with joystick timeouts and com radios recently which are fixed in 3.965. Don't know if your issue is related to this but just in case.Bill

Bill, thanks for the help. Unfortunately the 3.965 makes no difference.The problem must be to do with Windows 7 windows management. If I right click on the windscreen of the 2d cockpit and select "undock window", i get a window of the outside scene, but with a normal microsoft windows border round it. A mouse click on this does not create the stuttering. This only appears when the outside view and the cockpit windshield panel are "undocked ie the nornal 2d cockpit view..