I am unable to restore my full screen. It appears stretched with blackness on top and bottom. How can I fix this?
Thank you

Without knowing the specific monitor, what follows is a general approach to troubleshooting. First determine if the issue is the result of mis-configuration or malfunction. Was the resolution or refresh rate recently changed in the operating system? If so, the image's extents may need adjustment with the monitor's control dials or button's. CRT type monitors usually have one or more dials or buttons for adjusting the vertical image height and other aspects of the image, often through an onscreen display. LCD monitors usually have an "Auto" button that will make the monitor optimize the received video signal to fit the full image area. Another possible location for adjustments may be a software utility associated with the video adapter. If these types of image controls have no effect on the image height, the monitor may be defective. If another monitor is available, the video signal itself may be verified. More information concerning the events leading up to the monitor's current state would be useful.