Hi Abdul! Did you set the Rendering engine to Vray (@3:52) and did you load the default Vray settings? (@ 4:36). Try to make a render just with the default settings loaded, it should render 800x600 pixels. Now open up the Output tab from the Vray Options and deselect "override Viewport" and redner again. Now it should render the size of your current view port selected. The check box "Override viewport" controls if you either want to use Vray's render size or your current viewport's size. Let me know if it worked and good luck! Cheers