IBMDA400 Provider Returns Question Marks in Some Fields Instead of Data from AS/400 File Using MS Access VBA

Public Function AS400GetData(ByVal strUserName As String, _
  ByVal strPassword As String, ByVal strSQL As String, _
  ByVal strSystem As String, ByRef avarData() As Variant) As Boolean
' set up error handling
On Error GoTo ErrorHandler
    ' set the initial state of the function
    AS400GetData = False
    ' open a connection to the AS400
    Dim cnn As New ADODB.Connection
    cnn.Open "Provider=IBMDA400;Data Source=" & strSystem & _
        ";User ID=" & strUserName & ";Password=" & strPassword & ";"
    ' using a recordset, get the data and field names
    Dim rst As New ADODB.Recordset
    With rst
        ' open the recordset
        .Open strSQL, cnn
        ' if data was found,
        If Not .EOF Then
            ' get the data
            avarData = .GetRows
            ' eliminate leading and trailing spaces in the data elements
            AS400TrimData avarData
            ' indicate data was retrieved
            AS400GetData = True
        End If
        .Close
    End With
    ' close the connection
    cnn.Close
    ' clean up
    Set rst = Nothing
    Set cnn = Nothing
ExitHere:
    Exit Function
ErrorHandler:
    MsgBox "Error:" & err.Number & vbNewLine & _
        "Description:" & err.Description & vbNewLine & _
        "From:" & err.Source, vbExclamation, _
        "AS400GetData Failed"
    Resume ExitHere
End Function