For ArcGIS 10.4.0

Note: GeoWEPP for ArcGIS 10.4.0 is compatible with ArcGIS 10.4.0.

Detailed Manual (links to ArcGIS 9.x version overview)
GeoWEPP for ArcGIS 10.1 Version Overview Manual (links to ArcGIS 10.1 version overview)
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For GeoWEPP for ArcGIS 10.4.0 version, please refer to the manuals for the previous versions listed above. There have been interface changes but the basic functions haven't been changed. A new detailed manual with the current interface will be released in the near future.