If you need technical help with logging in to your Linksys extender, Double-check the Login Credentials: Ensure that you are using the correct username and password to log in to your Linksys extender. By default, the username is usually left blank, and the password is "admin" (without the quotes). If you have changed the login credentials in the past and can't remember them, you may need to perform a factory reset on the extender.