Modem diagnostics overview
You can verify that your modem is working properly by using the diagnostics that are
available through Phone and Modem Options in Control Panel. To open Phone and
Modem Options, click Start, click Control Panel, click Printers and Other
Hardware, and then click Phone and Modem Options.
When you query a modem, Windows XP tries the following commands and displays
مودم ها (modems)