Does setting Data Validation work with Excel actxserver

Has anyone got this to work from a program? I have tried the statement below in a program (100% failure), from the command line (~90% success), and in the debugger (~50% success). I have tried putting a .Delete call in first and have tried a .Modify call instead of the .Add?

Thanks.

hs is a Range object; ProType is a defined name in the workbook (which is workbook scope) and is defined as a range on a sheet. K>> hs.Range(dRange).Validation.Add(3, 1, 1, '=ProType') Error using Interface.Microsoft_Excel_14.0_Object_Library.Validation/Add Error: Object returned error code: 0x800A03EC