A new window will open containing the eBay log-in screen. Log in and follow the dialogue to authorize CartRover to act on behalf of your eBay account. When complete, return to the CartRover window and it will let you know if the authorization was successful. If a new window does not open, please make sure you do not have a pop-up blocker enabled.
If it says you have signed out of eBay, instead of bringing you to an eBay log in screen, close your browser along with CartRover, and try again.