If you are unable to reach the tplinkrepeater.net interface, there are various troubleshooting steps that you can take to resolve the issue. If you receive an error message from Tp-link, it may be the case that you cached the IP address of a range extender. Try deleting the cache memory and history of the browser, and then try to access the web interface of the Tp-link range extender. Make sure you are interacting with the web interface of your range extender only through the approved browsers.