On Parallels desktop for mac, my screen resolution on the virtual machine keeps flickering from one size to the other. I'm running Windows Vista Basic and I haven't had this problem until recently when I decided to download Parallels Tools. Another problem ever since I downloaded Parallels Tools is that when I go in to fullscreen mode, the edges of the screen are black (about an inch on every side is black) and when I hover over the black space, it shows the mac menubar? (The bar at the top of my screen) Any help towards rectifying these problems is very much appreciated.