Dear MBoucher, I had exactly the same problems as LAYLA using ArcHydro v10.2 on ArcGIS V10.22 I tested all the solutions you proposed without changing either ArcHydro or ArcGIS version. None of the solutions did not yield results and I always get the same message "HRESULT E_FAIL error returned from a call to a COM component" when i use DEM Reconditionning I have not been tested LAYLA's solution because I do not have a computer with ArcGIS 10.1 installed. My second computer have an ArcHydro v1.4 with ArcGIS v9.3.1 where everything works perfectly. So I think this is a real BUG in the ArcHydro v10.2 Sincerely Yours. NB : I'm using French ArcGIS and sorry for my bad English.
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