You have to either select existing printer form with the size that fits your requirements or create custom one as shown in How to add/delete custom printer forms under Windows NT/2K/XP FAQ #21202


>I want to print cheque. For this I scaned cheque and paste the image in report writer. The cheque size is Height=3.5 and Widht=6.5, I am using Letter size landscape paper. In report page setup I adjust Height=3.5 and Widht=6.5, but in print preview the paper letter appears instead of my given size, Height=3.5 and Widht=6.5
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>How to show paper size Height=3.5 and Widht=6.5