Why isn't my PHP page displayed inside the html-include macro?

[Fynn K]

Hello,
I tried to include an external php page inside Confluence using this tutorial:
https://confluence.atlassian.com/display/CONFKB/How+to+Use+PHP+inside+Confluence+Pages

When I try to use a php page the Confluence page just stays empty (Not even an error code).
With html pages it does kind of work, even though the css is not applied.

Anybody has got an idea why?

PS: The page(s) that I am trying to display are all located on a local server.

[Fynn K]

I found a workaround to the problem by using the normal html-macro combined with an iFrame, instead of using html-include.
<iframe src="myURL" width="300" height="300" frameBorder="0">Browser not compatible.</iframe>