In some case, COM1 port is not available on a PC (I had the issue with a DELL laptop that were lent to me by one my customer). The method described in Connecting the Symbian emulator to the Internet could not be used as is to debug my Symbian code.

The solution consist in configuring the Emulator so that it will use another COM port (COM2 in my case). This can be done by editing the CommDB configuration file. This can be done using the T_EDITDB.EXE application (in C:\Symbian\6.1\Series60\Epoc32\Release\wins\UDEB ). It is easier to use setupcomms.bat (located in C:\Symbian\6.1\Shared\EPOC32\Tools but accessible from anywhere since this directory shall be in your path):
  open a dos box
  run setupcomms.bat: this will launch the emulator and start a console application that will allow to change the communication settings of your SDK:

  select Modems: a new screen with the default modem details appears
  move down to the second line whose value shall be COMM::0 by default:

  replace COMM::0 by an appropriate value for your system (COMM::1 for COM2, COM::2 for COM3,...)
  save and exit
  configure Virtual Port to redirect COM2 to COM3 (or any other port you want to use!)
  configure mRouterLite to use COM3

Here it is.... your app should be able to access the Internet.