Car Navigation simulator

Hi, I am creating a simulator for a car navigation, where basically I am using street maps. in the project, I have many 500x500 bitmap maps. so, I am using tiling techniques to combine all the maps together. here is the map layout, where I have 9 column tiles and 9 row tiles. 0---------->4500 | | | | 4500 The screen resolution is 1024x768 (the viewport) 0----->1024 | | | 768 so, what I did is to display from 0 to 1024: - use 2 500x500 bitmaps - then using the rect to get the other 24 pixel. and for the 0 to 768: - Use 1 500x500 bitmaps - the using the rect to get the 268 pixel. however, it gives me error on the second one (the one for the row). Direct3D8: (ERROR) :NULL surface interface specified. CopyRect fails Direct3D8: (ERROR) :NULL surface interface specified. CopyRect fails Direct3D8: (ERROR) Rect doesn''t fit inside the surface Direct3D8: (ERROR) :CopyRects failed First-chance exception in DirectX_MFC.exe (KERNEL32.DLL): 0xC0000005: Access Violation. Thanks in advance. Tony