Android browser rejects router admin page over HTTPS certificate

The most likely cause is that the router uses a self-signed certificate that Android does not trust, so Chrome or Samsung Internet shows a warning and may hide the "continue anyway" option. 1. Try the browser's advanced option first. In Chrome, tap "Advanced" and then "Proceed to [address] (unsafe)". If that link is missing, tap anywhere on the warning page and type "thisisunsafe" (no spaces) on the keyboard. This works in Chrome on many versions. 2. If you still can't get past it, open the router's address using plain http:// instead, for example http://tplinkrepeater.net or the IP shown on the router's label (often 192.168.0.1 or 192.168.1.1). This is less secure on public networks but is generally fine on your home network for setup. 3. Try a different browser. Firefox for Android lets you accept the risk through "Advanced" and "Accept the Risk and Continue," which is often easier than Chrome. 4. Make sure you are on the router's Wi-Fi or connected by cable, not on mobile data. Mobile data can send you to a different site entirely. 5. Clear the browser's saved data for the router address, or use a private/incognito tab, then try again. 6. If the router was reset or its firmware updated recently, the stored certificate may have changed. Restarting the phone's browser or the router often clears this. 7. As a last resort, use the manufacturer's phone app, which usually bypasses the browser entirely. I'm not certain which exact browser or router model you have, so these steps may vary. Warnings on a local router are common and usually harmless, but avoid entering a password if you are on a network you don't control. If none of this works: check the router manufacturer's support page for your model's Android setup instructions, or contact their support with the model number and browser version.