SoOffscreenRenderer fails to render a texture on a cube

I was trying to render a texture on a cube using SoOffscreenRenderer
class.

Is this class is sup****ted by Open Inventor, when I do compilation, I
get a error warning as " SoOffscreenRenderer not yet ****ted to the
WIN32 platform, using stubs!"

Is there any known reason for the failure of offscreen rendering ?

I am trying the offscreen rendering in the following way.

SbView****tRegion aView****t( 512, 512 );
SoOffscreenRenderer* offscRender = new SoOffscreenRenderer(aView****t);
offscRender->setComponents( SoOffscreenRenderer::LUMINANCE );
SoSeparator* root = new SoSeparator;
root->ref();

SoPerspectiveCamera* camera = new SoPerspectiveCamera;
camera->position.setValue( -0.2, -0.2, 2.0 );
camera->viewAll(root,aView****t );

root->addChild( camera );
root->addChild( new SoDirectionalLight );

SoTexture2* texture = new SoTexture2;
texture->image.setValue(SbVec2s( 3, 2 ), 1, image);
root->addChild ( texture );
root->addChild ( new SoCube );
if( !offscRender->render( root ))    // It fails in this step.