This is the error:
System.Runtime.InteropServices.COMException (0x80004005): Error HRESULT E_FAIL has been returned from a call to a COM component.
at ESRI.ArcGIS.Geoprocessing.GeoProcessorClass.Execute(String Name, IVariantArray ipValues, ITrackCancel pTrackCancel)
at ESRI.APWR.ApHydro.ArcHydroOp.DEMReconditioningGP(ApLayers apLayers, Double numCellsBuff, Double sharpDrop, Double smoothDrop, Boolean raiseNegative, Boolean bUsingStreamGridInput, ITrackCancel& trackcancel, IGPMessages& messages, String& exMessage) in C:\Builds\HydroSolutions\10.5_ArcHydro\Sources\ArcHydroTools\src\ApHydro\ArcHydroOp.vb:line 63089
Failed to execute (DEMReconditioning).
Failed at Mon Aug 26 20:36:03 2019 (Elapsed Time: 14 minutes 56 seconds)