Rendering materials - VR materials won't appear

[loza20]

hey SUcation members,
my name is aya i am from egypt .. i am a newbie at sketchup ..
so i started to put materials on my project with light adjusments
yet when i render the materials doesn't appear on the rendering window and it turn out to be like this image below .. any advice ??
thanks ..

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[rspierenburg]

Check in Vray options under "Global Switches" to see if override materials is turned on.