To modify the Remote Desktop Connection default port from 3389, do the following:

1. Launch the Registry Editor (regedit)
2. Locate the following key in the registry:
   HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\TerminalServer\WinStations\RDP-Tcp\PortNumber
3. On the Edit menu, click Modify, select Decimal, then type the new port number
4. Click OK.
5. Quit Registry Editor.

NOTE: When you try to connect to this computer by using the Remote Desktop connection, you must type the new port.

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

WARNING: The Remote Assistance feature in Windows XP may not work properly if you change the RDP listening port

Want to enable SMTP authentication for your email, here is how to do it in a variety of clients.

Microsoft Outlook 2002 (XP) and 2003

1. From the Tools menu, choose E-mail Accounts.
2. Click in the circle beside “View or change existing e-mail accounts.” Click Next.
3. Click the email account you wish to modify and then click Change.
4. Click More Settings.
5. From the tabs along the top, click “Outgoing Server.”
6. Check “My outgoing server requires authentication”.
7. Also, make sure to check “Use same settings as my incoming mail server.”
8. Click OK.
9. Click Next.
10. Click Finish.

More…

This works in all version of Windows.

Under run (on the start menu) type:
cmd or command

Under the Start menu:
Start -> All Programs -> Accessories -> Command Prompt