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.