I have a DEM with values that range from 0 to 1040. I'd like to create a layer with the flow directions by means of the Flow Direction tool in the Hydrology section of the ArcToolbox. However, when I try to do so, it creates a raster with only one value: zero. I'd like to have a raster with the values 1, 2, 4, 8, 16, 32, 64, and 128.
Does anyone know what I'm doing wrong, and how my mistakes can be repaired? Here are some screenshots of what I tried: