One of the wireless routers known to work well with Nintendo DS (and hence often recommended) is 3Com’s wireless router model# 3CRWE554G72TU.

Configuring your Nintendo DS to work with your 3Com wireless browser is rather easy. All you need to do is first figure out how your 3Com router is setup (IP address, password, SSID, WEK Key etc.), or reconfigure it afresh; and then mirror those settings in your Nintendo DS. Once you have matched those settings on your devices (wifi router, and your Nintendo DS), you will be all set to play online using Nintendo WFC.

To review/confirm how your 3Com wireless router is setup, simply power it up and launch your Internet browser (Internet Explorer, Firefox, Opera, etc.) on your computer. Enter http://192.168.1.1 in your web browser's address (URL) bar, and you will be connected to your wireless router's built-in Web Server.

If you are unable to login to your 3Com Wireless gear, it may be because you are typing-in incorrect authentication (username/password) details. Double-check your password (if any), and verify that neither the CAPSLOCK key on your keyboard is “On,” nor one of the SHIFT keys on your keyboard stuck in pressed-down state.

Considering that many administrators restrict how (using only wired, terminal, or wireless access), and from where (using filters based on IP addresses, MAC Addresses, or only from select computers) various devices can be configured, it may be quite possible that you are not even reaching the device in question. It may be helpful, therefore, to try to login using a wired (LAN based, or Terminal/Serial Port) access before doing a brute-force factory reset on your 3Com gear.