@tig said:

Have you tried messing with the OpenGL settings in the Preferences dialog.
There are various options, including switching hardware acceleration off.
Try combos of all of them and restart Sketchup each time and see what changes, if anything.
Does your graphics-card's control-panel allow Sketchup to adjust settings.
Have you tried setting Sketchup to 'run as administrator' etc ?

Thank you TIG.. Your last advice worked for me.. I ran the program as administrator & Viola! The window appeared... Thanks again !