Getting an Error Object Not Found

Hi All,

Trying to execute Dynamic Descriptive Program

SystemUtil.Run"C:\Program Files (x86)\HP\Unified Functional Testing\samples\flight\app\flight4a.exe"

1 .Dim Login,objuname,objpwd,objok
2. Set Login = description.Create
3. Set objuname = description.Create
4.Set  objpwd    = description.Create
5.Set objok = description.Create
  6.Login("text:").value="Login"
  7. objuname("attached text:").value="Agent Name "
  8. objpwd("attached text:").value="Password"
  9. objok("text:").value="OK"
  10.Dialog(Login).Activate
  11.Dialog(Login).WinEdit(objuname).Set "shiva"
12.  Dialog(Login).WinEdit(objpwd).Set "mercury"
  13.Dialog(Login).WinButton(objok).Click

"GETTING ERROR AT LINE 10 AS "Cannot i"dentify the object "OK" (of class WinObject). Verify that this object's properties match an object currently displayed in your application"

Can anyone help