Define Project本地服务包如何在arcgis runtime .net 100.6调用？

你好，我用arcmap 10.2的toolbox->data management tools->projections and transformations->Define Projection对一幅未设置投影坐标系的影像DOM设置投影坐标系，执行成功后将它以geoprocessing package的方式生成gpk(勾选"support Arcgis runtime").然后在arcgis runtime .net 100.6启动此服务，调用代码片段如下：

GeoprocessingParameters gpParams = new GeoprocessingParameters(GeoprocessingExecutionType.AsynchronousSubmit);
gpParams.Inputs["coor_system"] = new GeoprocessingString(projectString);
gpParams.Inputs["in_dataset"] = new GeoprocessingFeatures(new Uri(tifPath));
// Create the job
m_gpJob = m_gpTask.CreateJob(gpParams);

执行后出错，麻烦帮我看看哪里出错了．谢谢．出错信息为：Illegal state: Server job has failed. Invalid return value: c:\users\peter\appdata\local\temp\arcgisruntime_28976\defineprojection_dom\jobs\defineprojection_dom_gpserver\j98a707d142604f029a969ffa2d886c9e\scratch\dom.tif.