Reseting the Enable Password
From Peter Pap's Technowiki
1. Disconnect the switch from it's power source.
2. Hold down the mode button on the front and connect the power cable.
3. When you see the 'switch:' prompt, do the following:
switch: flash_init switch: load_helper switch: rename flash:config.text flash:config.backup switch: boot Would you like to enter the initial configuration dialog? [yes/no]: no
4. Enter enable mode and reset password.
switch: en switch# rename flash:config.backup config.text switch# copy flash:config.text system:running-config switch# config t switch(config)# no enable secret switch(config)# exit switch# wr mem switch# config t switch(config)# enable password somepassword