The Linksys extender login details are case-sensitive; you need to use them without any mistakes in spelling. That’s why, you must be aware of the default login credentials including the username and password. You might be unaware of how to get them, but, don’t worry, the manual setup guide will inform you about them. That guide will walk you through the basic details of your device and even some setup tips. So, once you receive your device, make sure to go through the guide to get familiar with those details. Although the default username and password of Linksys almost is the admin that you need to use for the first-time login. However, once you are done with the entire setup process, try to change those details immediately. As the default details are easy to access for external or unauthorized users, they can misuse your network. So, change the username and password and make them unique and strong enough to prevent those users.