>>Try CommandType.CmdText (or however it called in C#) instead of CommandType.StoredProcedure.
>
>It is CommandType.Text, but that doens't work. Same error. I should have said I tried that.

You could have not just set it at all, and let ADO figure out what it is. ADO will successively try each type until it succeeds. It can be a performance hit, but it works.