哪裡有錯??(編號:7305)

我想把Client傳回來的資料自動顯示在grid裡,程式如下:Private Sub tcpServer_DataArrival(index As Integer, ByVal bytesTotal As Long)
Dim strdata As String
 Dim n1 As String
 tcpServer(1).getdata strdata
 n1 = Mid(strdata, 1, 1)
 Select Case n1
 Case "a"
  txtname.Caption = Mid(strdata, 2)
  Call nex
 Case "b"
  txtip.Caption = Mid(strdata, 2)
 Case "c"
  txttotal.Text = Mid(strdata, 2)
 End Select
End Sub
Sub nex()
rs.AddNew "username", txtname.Caption
End Sub
卻出現 沒有設定物件變數或with區塊變數的錯誤訊息(err91)
但若設定一個button,如下:
Private Sub Command1_Click()
Call nex
End Sub
卻可以將傳回資料顯示在grid裡,但不想用手動來新增資料.
不知程式哪裡錯了????