SOLVED: How to Set the IP Address on a 3Com Switch

There are serveral ways but, if you have a serial console cable you can set the IP using the following process:

1. Get a serial console cable.  Note that I went through several of them before I found one that would let me SEND characters to the device; I could see the switches boot activity but nothing I typed would appear on the console window… so if you have this problem, get another cable!
2. Get a terminal program.  Windows Vista and 7 removed HyperTerminal (which is quite annoying) but you can download a free, fully functional version for 30 days from hilgraeve.com/hyperterminal-trial .
3. Start your HyperTerminal using the following settings: connect using COM1 (or whatever port you are using) 19 200 bits/sec 8 data bits No parity 1 stop bit No flow control
4. Power up your 4200G (or similar aged 3Com switch)
5. In the Hyperterminal Window you will see something like, and you will have just a second or two press CONTROL+B to enter the book menu:
   Starting……
   ***********************************************************
   * * * Switch 4200G 24-Port BOOTROM, Version 1.00
   * * * ***********************************************************
   Copyright (c) 2004-2005
   3Com Corporation and its licensors.
   Creation date : Nov 20 2006, 17:02:48 C
   PU type : BCM5836
   CPU Clock Speed : 200MHz
   BUS Clock Speed : 33MHz
   Memory Size : 64MB
   Mac Address : 0017e01f7a40
   Press Ctrl-B to enter Boot Menu… 2
6. type:
   system-view <enter>
   interface vlan 1 <enter>  
   ip address xxx.xxx.xxx.xxx mmm.mmm.mmm.mmm <enter>
   save <enter>
7. type
   quit <enter>

Note that the X’s are the address you want to assign and the M’s are the subnet which is often 255.255.255.0

see: http://forums.techguy.org/networking/981098-3com-4200g-switch-part-3c17660.html