“Parameter ?_1 has no default value” error when ExecuteReader

Question

Having problem with the code below in a web service. Have searched for a solution but nothing that I have seen seems different to what I am doing below.

NB: The

Answer 1

What you have looks correct with the "?" as the parameter place-holder for the parameters added to the command. You currently have the parameter identified as OleDbType.VarWChar. Is that intended? Are you dealing with unicode data? I suspect not in this case. Try changing to OleDbType.Char which also is represented to handle System.String values.

You could also make sure you are getting a string by using

AccountNo.ToString()