@ClankDan 

Hi

The label on the bottom of the product and the firmware page of the official website are marked EU or US. If the label on the bottom of your product shows EU, you need to download the EU firmware from the official website to update it.

If you are having trouble opening/accessing/reaching the web management interface, here are some tips for you:

    1) Please make sure your PC is connected to the main network of the Router, not a guest network or other networks, or simply using a wired connection to the Router.

    2) Use "Incognito mode" or "Private mode" in your browser.

    3) Try other PCs or phones.

    4) Disable the "Access Control" feature on the Router.

    5) If the TP-Link Router is working in AP mode, please confirm its IP address from the DHCP client list of your main router or use static IP address within your main router LAN subnet.