So you forgot your WLC password, eh? WLC version 5.1 and later, you can use the CLI from the controller's serial console in order to configure a new user name and password. Complete these steps in order to configure a new user name and password.
1. After the controller boots up, enter Restore-Password at the user prompt.
Note: For security reasons, the text that you enter does not appear on the controller console.
2. At the Enter User Name prompt, enter a new user name.
3. At the Enter Password prompt, enter a new password.
4. At the Re-enter Password prompt, re-enter the new password.
note: The controller validates and stores your entries in the database.
5. When the User prompt reappears, enter your new username.
6. When the Password prompt appears, enter your new password.
Note: For WLCs that run earlier versions of firmware (prior to 5.1), there is no way to recover the password.
If you use the Cisco Wireless Control System (WCS) in order to manage the WLC, wireless LAN controller Module (WLCM) or Wireless Services Module (WiSM), you should be able to access the WLC from the WCS and create a new administrative user without logging into the WLC itself.
Or, if you did not save the configuration on the WLC after you deleted the user, then a reboot (power cycling) of the WLC should bring it back up with the deleted user still in the system. If you do not have the default admin account or another user account with which you can log in, your only option is to default the WLC to factory settings and reconfigure it from scratch.