I have one domain (website) and one home computer. On my home computer I installed software for mobile recharge. This system has a static IP.
So I send a recharge request (HTTP request) to my home computer using my website. The concept is: Every request is processed and sends a response to my website. But whenever I send the request, the home system port 80 is blocked.
My home system has no firewall enabled and no anti-virus software installed. So why does my port 80 appear to be blocked?