I've been spending the last week or so learning how to program the Rpi3, and have so far had success. This is where I'm stuck at. I've set up an access point (here: https://www.raspberrypi.org/documentation/configuration/wireless/access-point.md), installed a webserver (like this: https://www.raspberrypi.org/documentation/remote-access/web-server/apache.md) and have made a basic website using the GPIOs and following this: https://www.instructables.com/id/Simple-and-intuitive-web-interface-for-your-Raspbe/
I've been saving images so I can always reset to a fresh start. Starting from a blank slate, I setup the access point, and installed the webserver (apache/php). I now want to make a captive portal (like this: https://pimylifeup.com/raspberry-pi-captive-portal/)
Everything seems to work until I try to start nodogsplash, I get the "iptables no chain/target/match" over and over when I try to start nodogsplash.
What do I do? I've tried changing the settings within the iptables (including reseting to defaults) but I don't know what I'm doing.