HTML include in header

[chikuru]

I want to add my custom header from an external HTML file.
I tried this one: https://www.vbulletin.com/docs/html/..._externalfiles

But I didnt got it work..

Can anyone help me how to properly include HTML external file

Thanks

[RobbieZ]

Have you posted in the correct section? This is graphics!

If it is the right area can you describe more of your problem and what you are trying to accomplish.