The ArcGIS Runtime SDK for .Net application is unable to create a LocalMapService for ArcGIS Pro map packages (.mpkx) and fails with the following error message, "Couldn't create SOC process."
This issue is not reproducible with ArcGIS Runtime SDK for .NET version 100.5 and Local Server version 100.5. Use the Package Map Geoprocessing tool and check the Support ArcGIS Runtime value on when creating the map package. When using ArcGIS Pro created packages, be sure to set the Platform Target to x64 in the Visual Studio project and set all values in the ArcGISLocalServer_100.5.AGSDeployment file to true.
Contact Esri Support Services if this issue is still occurring with version 100.5.