Website displays properly locally and remotely, but...

[Asatani]

I am running XAMPP 5.6 and experiencing a weird issue. If I preview my website locally (http://localhost/), it works as intended, all content is displayed. If I ask someone outside my network to view it (http://my.exte.rnal.ip/), their screenshot shows it to be working as intended, all content displayed. If I try to access it from another computer on my network (both http://my.inte.rnal.ip/ and http://my.exte.rnal.ip/), only text and table data are displayed, all images are broken and no scripts run. I want to edit and preview my website without having to be at my server computer, so this is issue is pretty inconvenient. Is there anything I can do to fix this?

Just to clarify, all of my content uses relative pathing, not absolute. Everything displays correctly from outside my network, just like it does when viewed locally.

[Altrea]

Use a debugging tool like Firefox Firebug, Chrome Developer Tools or something similar to display all requests and their responses.
Especially interesting informations are Which ressource URLs are used and Which HTTP Status codes are responded.

[Nobbie]

The only thing which comes to mind: maybe you have some certain "Require" (or "Allow From") Clauses in your Apache configuration, which denies access from inside your LAN. You should find out it anyway via studying the access log and the error log. And/or there might be some similar rules in your local firewall.