First, rule out the problem is the file by running RECOVER command (instead of OPEN) or AUDIT command if you are already in the file (remember to answer Yes to fix any errors found).
Another fix you can try is to turn off video card hardware acceleration in Windows: In WindowsXP for example, this is found in Control Panel> Appearance and Themes> Display> Settings Tab> Advanced Button> Troubleshoot Tab> Hardware Acceleration slider:
◦
