It's your video card.
In Windows, Right click your mouse on the desktop and select Properties. Go to the Settings tab and click the Advanced button below. Go to the Trouble shooting tab and move the slider one notch. Then restart Mastercam and try it again. If your still having the same problem, go back and move it doen another notch.
What Video card do you have. If it's the intel video chip set, you'll probably end up moving to the bottom to get it to work. Not Mastercam's fault. The Intel video chip is known to suck.
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