窗体不能登陆

Private Sub login_Click()
   Dim str As String
   Dim rs As New ADODB.Recordset
   Dim fd As ADODB.Field
   Set cn = CurrentProject.Connection
   logname = Trim(Me!username)
   pass = Trim(Me!pass)
    If Len(Nz(logname)) = 0 Then
                MsgBox "请输入用户名"
        ElseIf Len(Nz(pass)) = 0 Then
                MsgBox "请输入密码"
        Else
            str = "select*from  密码表 where 用户名=' " & logname & " ' and  pass=' " & pass & " '"
            rs.Open str, cn, adOpenDynamic, adLockOptimistic, adCmdText
        If rs.EOF Then
                        MsgBox "没有这个用户名或密码输入错误，请重新输入"
                        Me.username = ""
                        Me.pass = ""
                Else
            Set fd = rs.Fields("权限")
                     If fd = "管理员" Then
                                DoCmd.Close
                                DoCmd.OpenForm "cy-1"
                                MsgBox "欢迎您，管理员"
                        Else
                                DoCmd.Close
                                DoCmd.OpenForm "主窗体"
                                MsgBox "欢迎使用管理系统"
                       End If
                End If
        End If
End Sub

各位老师！先谢谢！谁能解？