I try using the internet explorer app, but i just get an error message saying that the application is not supported.
I see it being done here:https://www.scirra.com/forum/xbox-360-039-internet-explorer-039-app-amp-html5_t74045, is there any reason why it wouldn't work now?
Develop games in your browser. Powerful, performant & highly capable.
What webserver software are you running it on?
Consoles are usually locked down for security reasons, so they may well have turned off browsing sites on the LAN.
Construct 2 never really supported the Xbox 360 anyway. Xbox One is supported though!