php - Why when add to web page don´t work on hosting?

I am developing a simple webpage at
hostgator.com.
I have the standard headers, but when I add the following
line:

            encoding="utf-8"?>
            

the page does not
work. I would like why.

This is the full
header:

            version="1.0" encoding="utf-8"?>
            XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1
            /DTD/xhtml1-strict.dtd">
            lang="es" xml:lang="es"> 
... rest of code
            ...

The server returns
me a blank page

/>

Issue
solved: The PHP short tags was open.